CHARACTERIZATION OF BEHAVIOR 

OF HUMPBACK WHALES IN HAWAIIAN WATERS

Prepared by: 

James D. Darling 

Photographs and Video by Charles “Flip” Nicklin

West Coast Whale Research Foundation 

206 - 2199 Broadway 

Vancouver, B.C. V6K 2F1 

and 

Whale Trust 

300 Paani Place 

Paia, Maui HI 96779 

www.whaletrust.org

For: 

Hawaiian Islands Humpback Whale 

National Marine Sanctuary 

Division of Aquatic Resources 

Department of Land and Natural Resources 

1151 Punchbowl Street, Room 330 

Honolulu, Hawaii 96813 

December 2001 

This report is used for documentation and timely communication of preliminary results. While the report has not 

undergone complete formal review and editing, it reflects sound professional work and may be referenced in 

scientific and technical literature. 
 i 

EXECUTIVE SUMMARY 

Humpback whales make annual migrations to winter assembly areas in 

subtropical and tropical waters to mate and, after a year gestation, give birth. The main 

Hawaiian Islands are the largest such assembly area in North Pacific. Since the late 1970s 

humpback whale research in Hawaii has been at the forefront of the investigation of 

reproductive behavior patterns of this species. This report reviews available information 

and summarizes our current understanding of the behavior of humpback whales in 

Hawaii. 

Humpback behavior patterns in Hawaii represent a continuum of reproductive 

activities that begin on late season feeding grounds and occur throughout the migration. 

In Hawaii, whales are found around all the main islands, with concentrations on shallow 

banks within the Four Island Group, Penguin Banks and to a lesser degree off the Kona 

coast and Kauai. It is apparent whales circulate freely throughout the islands, although 

questions remain as to if differential use of specific locations occurs. Cows with newborn 

calves are more likely to be found in shallow, inshore waters than the general population. 

Humpback whale abundance peaks in February-March, but whales are common from 

December through May and seen as early as September and as late as June. The arrival 

and departure of whales is segregated to some degree by age, sex and reproductive 

condition, with strong suggestions that, with the exceptions of some males, many whales 

are present for short periods relative to a five-six month long season. 

Female reproductive cycles govern much of the humpback whale behavior in 

Hawaii. Humpback whales give birth on the average every two-three years, although 

postpartum estrus is common with annual birth occurring in some portion of the 

population. The sexual cycle peaks during the three-five winter months, with peak 

ovulation in January-February. Females are seasonally polyestrus, undergoing several 

cycles if pregnancy does not occur. Peak ovulation period coincides with most behavioral 

activity in Hawaii including the peak of singing, male competitive and aggressive 

behavior, and transience of individuals among groups. With a 50:50 sex ratio, and the 

average birth rate two-three years, many more mature males than fertilizable females are 

present in any one breeding season, leading to increased competition among males. 

It is generally agreed that humpbacks follow a polygynous or promiscuous mating 

system. The former implies that males monopolize females in some way; in the latter they 

do not. Mating system hypotheses include dominance polygyny where males develop and 

maintain, through display and fighting, a hierarchy for access to females; and lek 

polygyny where males assemble and advertise to females through song. A further 

emerging hypothesis proposes formation of male coalitions and cooperation to access 

females. All these hypotheses require further testing. 

Most male behavior patterns, interactions and associations are short-lived, lasting 

only minutes to hours, with the animals apparently orienting to any female in estrus. 
 ii 

Earlier studies emphasized male antagonism and avoidance of each other; more recent 

studies report non-agonistic male-male interactions. Male behavior patterns include 

singing; interaction with singers, at times forming all male pairs, trios or larger groups; 

and escorting or guarding females, defending or challenging the escort position with a 

variety of agonistic behavior including displays, sounds and physical clashes that may 

result in bloody wounds. There are some suggestions of cooperative and even care-giving 

behavior amongst some males. 

Female behavior patterns are set in two contexts: mating or birth and newborn 

care. Some portion of females undergoes postpartum ovulation and are involved in both 

activities in one season. Little is known about female mating strategies and behavior; 

however, this likely includes maximizing contact with males, minimizing contact and 

potential competition with females, and accomplishing mating in as short time as possible 

for energetic considerations. Female behavior may include acceptance of the male escort, 

leading or being chased by multiple competitive males, and mating. Female-female 

associations are rare on the breeding grounds. A typical behavior flow begins with a 

female-male pair in apparent calm union; this pair joined by other males often leading to 

competitive groups; and eventually the group breaking up leaving a pair again, which may 

or may not include the original male. Female behavior may influence the selection of a 

mate through encouraging competition and accepting/rejecting copulation. It has been 

proposed that females select males based on song but there is no evidence to support this 

hypothesis. 

Female humpbacks in Hawaii are involved in birth, nursing and protection of 

young. These cows with newborn often occupy shallow, inshore waters presumed to 

separate them from mating activity and harassment of males, more turbulent offshore 

conditions, and predators. Birth has not been observed, although circumstantial evidence 

indicates it peaks at the time of year whales are in Hawaii. With sightings as early as 

December, cows with newborn peak in numbers in February-March, and are usually the 

last groups seen in May and June. Cow/calf pairs usually maintain an active separation 

from each other. Cows with calves apparently travel and circulate through the region like 

other whales. Travel is the most cow/calf common behavior. When resting the cow often 

lies in a horizontal position at 30-70 feet below the surface with calf under her head or 

body. The calf surfaces every five to six minutes, circles, and dives back towards the cow, 

with the cow surfacing every 10-20 minutes. Suckling occurs when cow/calf is either 

stationary or traveling. Play is a common activity with the calf mimicking most adult 

actions and postures. Some sounds by the calf and between cow and calf have been 

documented, but relative to males they are quiet. It has been proposed that the single male 

escort is accepted by the cow as it may offer indirect protection from groups of males. 

Juveniles, ranging from yearlings to four to five years old, make up a portion of 

the Hawaiian humpback population; little is known of their behavior patterns. They are 

found on the periphery of adult groups, in association with adult males including 

involvement in apparent sexual activity, in juvenile pairs, and alone. One observation 

reports a sub-adult attempting to feed in Hawaii. 
 iii 

 

We may have a greater understanding of humpback whale reproductive behavior 

than other whales; however, overall, our knowledge is still young and dynamic with many 

aspects at the hypothetical stage and others barely described. Streams of important 

investigation include the relationship of habitat and behavior, male and female 

reproductive strategies, and factors that affect birth and newborn success. 
iv 

CHARACTERIZATION OF BEHAVIOR OF HUMPBACK WHALES 

IN HAWAIIAN WATERS 

CONTENTS

EXECUTIVE SUMMARY.................................................................................................. i 

CONTENTS .................................................................................................................... iv

INTRODUCTION................................................................................................................1 

MATERIALS AND METHODS.........................................................................................2 

 Humpback Whale Studies Conducted in Hawaii.....................................................2 

 Humpback Studies in Other Regions.......................................................................3 

 Humpback Studies Based on Whaling Data ............................................................3 

RESULTS ......................................................................................................................6

 GENERAL BEHAVIOR – The Hawaiian Breeding and Nursery Grounds ............6 

 Definition and Boundaries ...........................................................................6 

 Local Movements and Use Patterns.............................................................7 

 Presence and Individual Length of Stay.......................................................8 

 REPRODUCTIVE CYCLES.................................................................................10 

 Sexual Maturity and Birth Rate .................................................................11 

 Timing, Duration and Recurrence of Estrus ..............................................12 

 MATING BEHAVIOR ..........................................................................................13 

 Male Behavior Patterns..............................................................................16 

 Singing ...........................................................................................17 

 The song.........................................................................................18 

 Interactions with singers ...............................................................19 

 Escorting/Guarding a female ........................................................21 

 Competitive/Agonistic behavior ....................................................22 

 Displays and fights.............................................................22 

 Competition for females ....................................................23 

 Social sounds .....................................................................25 

 All male group agonistic behavior.....................................25 

 Cooperative male behavior ............................................................26 

 Female Behavior Patterns ..........................................................................27 

 Female mating strategies................................................................27 

 Pair – Female with male ................................................................30 

 Females in competitive groups ......................................................31 

 Females choosing males via song? ................................................32 

 BIRTH AND YOUNG...........................................................................................33 

 Birth ...........................................................................................................35 

 Newborn behavior......................................................................................35 

 Acceptance of escort by cow with calf.......................................................37 

 Juvenile behavior .......................................................................................38 

DISCUSSION ....................................................................................................................39 

ACKNOWLEDGMENTS .................................................................................................41 

LITERATURE CITED (all included in Appendix 1) ........................................................41 
v 

APPENDICES ...................................................................................................................42

Appendix 1: Hawaiian Humpback Whale Behavior and Related Literature .....................43 

Appendix 2: Glossary of Humpback Whales Actions and Postures..................................53 

Appendix 3: Slide Transparencies and Video Clips of Behavior .......(separate from report) 

LIST OF TABLES 

Table 1. Definition, typical behavior and sex composition of humpback social units ........5 

Table 2. Reproductive cycle summary...............................................................................11 

Table 3. Mating system hypotheses ...................................................................................15 

Table 4. Behavior of females in the year previous to birth................................................29 

LIST OF FIGURES 

Figure 1. Hawaiian Island humpback whale distribution, primary study sites and 

 Hawaiian Island Humpback Whale National Marine Sanctuary boundaries........6 

Figure 2. Timing of humpback whale social and behavioral events in Hawaii ...................9 

Figure 3. Singer..................................................................................................................18 

Figure 4. Singer and joiner.................................................................................................20 

Figure 5. Cow/calf and escort (aerial view).......................................................................21 

Figure 6 Examples of agonistic displays............................................................................23 

Figure 7. Competitive group ..............................................................................................24 

Figure 8. Female - male pair ..............................................................................................31 

Figure 9. Cow with young calf...........................................................................................34 

Figure 10. Calf with young calf resting..............................................................................36 

Figure 11. Cow/calf and escort ..........................................................................................37 

Figure 12. Examples of humpback whale actions and postures ........................................55 
1 

CHARACTERIZATION OF BEHAVIOR OF HUMPBACK WHALES 

IN HAWAIIAN WATERS 

INTRODUCTION 

Humpback whales (Megaptera novaengliae) migrate between high latitude, 

summer feeding grounds, and subtropical or tropical winter assemblies for reproductive 

purposes (Scammon 1869, Kellogg 1928, Dawbin 1966). The Hawaiian Islands comprise 

the largest known reproductive assembly in the North Pacific Ocean. Currently, they are 

utilized by approximately four to six thousand whales (Calambokidis et al. 1997, Cerchio 

et al. 1998). The Hawaiian Islands seem to be the primary migratory destination for 

humpback whales from summer feeding grounds in British Columbia and Alaska, but it is 

also clear that the region is visited to some degree by whales from throughout the Pacific 

Basin (Winn et al.1981, Darling and Jurasz 1983, Payne and Guinee 1983, Darling and 

McSweeney 1985, Baker et al. 1986, Darling and Cerchio 1996, Calambokidis et al. 

1997, Salden et al. 2000, B. Mate pers.comm. 2000). Humpback whales assemble in 

Hawaiian waters to mate, and following a year gestation, to give birth and nurse newborn 

calves (Chittleborough 1958, Herman and Antinoja 1977, Rice 1978). 

The reasons humpback whales undergo this annual migratory cycle of many 

thousands of kilometers away from their feeding grounds are not well understood. The 

whales shift seasonally from a context of feeding, resting and net energy gain, to one of 

fasting, traveling, birthing, nursing, mating and significant energy expenditure (Scammon 

1869, Nishiwaki 1966, Clapham 1999). Consistent environmental conditions across 

winter assemblies are warm water (19-25°C) and banks of relatively shallow depth (<200 

m), which presumably offer significant survival benefits to the whales, perhaps especially 

mothers and newborn (Lockyer 1981). The winter assembly also serves the purpose of 

concentrating and mixing whales from seasonally separate feeding grounds, likely with 

important gene flow implications (Paslboll et al. 1995, Baker et al. 1998). 

In Hawaii and during the breeding season, humpback whales presumably pursue 

theoretical mammalian objectives of maximizing reproductive success (Emlen and Oring 

1977). Tenets typically include male strategies to maximize matings, and female 

strategies to select a “high quality” mate, while avoiding unwanted mating activity, 

particularly during newborn care (Jones and Swartz 1984, Taber and Thomas 1984, 

Smultaea 1994, Cartwright 1999). We expect male strategies to include seeking out and 

competing in some way for estrus females; and at the same time for females to engage in 

behavior to select, passively or aggressively, the most “fit” mates. As birth and newborn 

care are incompatible with mating behavior, females also behave to separate and protect 

young from male harassment, and prepare them for migration when they are just weeks 

old. Most humpback behavior patterns, communications and interactions observed in 

Hawaii are likely dedicated to one or more of these objectives. 
2 

Our understanding of humpback whale reproductive behavior has developed in 

two decidedly separate chapters. The first began in the 1930s, but primarily occurred 

through the 1950s and 60s. This involved the examination of thousands of whales, 

harvested by the whaling industry, to investigate the condition of reproductive organs, 

ovaries and testes, and status of the fetus (e.g., Chittlebourough 1958, Nishiwaki 1959, 

Dawbin 1966). While this work provided an invaluable framework for understanding 

reproductive cycles, virtually nothing was revealed of the actual reproductive behavior. 

The second chapter began in the mid-1970s with the development of the study of living 

whales in their natural habitat. From close surface and underwater observations and 

development of sighting and behavioral histories of specific whales identified by 

photographs of natural markings, the first descriptions of natural behavior patterns arose. 

Studies of humpback whales in Hawaii have been at the forefront of this second chapter 

of investigation into the reproductive behavior of this species. 

The sea conditions in Hawaii, including calm lees protected from trade winds 

combined with warm, clear water, and easy access to high densities of whales make it a 

remarkable location to study whale behavior. Since the first trials to study individual 

living whales in the 1970s, there has been a steady stream of research, photography and 

film, resulting in many first-descriptions, new insights and hypotheses on humpback 

whale behavior. Several research programs initiated in the late 1970s and 1980s such as, 

the Center for Whale Studies (D. Glockner-Ferrari and M. Ferrari ), University of Hawaii 

(L. Herman and graduate students), and Hawaii Whale Research Foundation (D. Salden) 

have continued through the present, with remarkable longitudinal data sets and ongoing 

contributions. Most current studies (11 Federal Permits in 2001) are multi-year programs 

moving through larger research questions in stages. When combined with similar studies 

in such regions as New England, the West Indies, Alaska, Mexico, Japan, and eastern 

Australia, this work has led to an unprecedented surge in the knowledge of humpback 

whale behavior and almost a complete revision of our understanding of these animals in 

the past two decades. 

The purpose of this report is to review all the available information and 

characterize behavior patterns of humpback whales in Hawaiian waters. 

MATERIALS AND METHODS 

The information synthesized here comes from three sources listed below. 

Humpback Whale Studies Conducted in Hawaii 

These studies make up the majority of the content of this report, taken from over 

50 references listed in Appendix 1. Papers published in technical journals and books were 

the primary source of information, followed by unpublished reports and graduate 

dissertations that contained otherwise unavailable information. Conference abstracts were 
3 

used when no other source of unique information was available. Personal 

communications were included when offered, especially when they updated published 

information. 

These materials were reviewed, summarized, and then synthesized in an attempt 

to deliver the current state of knowledge on humpback whale behavior. A large amount of 

information is contained in these works, with much overlap in some areas, especially in 

the earlier whale studies out of Hawaii (1979-85). In cases where all relevant studies 

essentially agreed, generalized statements are made and all of the references that provide 

some information or discussion on the topic are included. In cases where differences in 

interpretations and alternate hypotheses have developed, the arguments are discussed, and 

questions that remain open noted. Finally, cases are noted where initial published 

speculation has since been proven incorrect or misleading. 

Humpback Studies in Other Regions 

In addition to information from studies based in Hawaii, applicable studies from 

other regions are presented, many of which have addressed similar or related research 

questions to Hawaii. For example, Alaskan studies have provided important related 

information on birth rates or singing behavior (e.g., Straley et al. 1998, McSweeney et al. 

1989); in the North Atlantic studies off New England and the West Indies based on long 

term research programs and sighting histories, and the collaborative YONAH project that 

pooled photo-identification and genetic data from around the Atlantic rim (e.g., Mattilla 

et al. 1987, Clapham et al. 1992) have greatly enhanced our understanding of humpback 

reproductive behavior patterns observed in Hawaii. Australian studies have focused on 

humpback behavior during the migration to the breeding grounds, and have provided a 

critical perspective on reproductive behavior patterns including song (e.g., Brown and 

Corkeron 1995, Noad et al. 2000). 

Humpback Studies Based on Whaling Data 

 Prior to studies on living whales, virtually all life history parameters were 

constructed from the examination of reproductive organs of a large series of specimens 

resulting from whaling operations. This information is invaluable in the description of 

reproductive cycles, and for providing a physiological context for behavioral 

observations. Included is information from studies in the North Pacific (Nishiwaki 1959-

61, Tomlin 1967), Australia (Chittleborough 1958, 1965), New Zealand (Dawbin 1966), 

and Africa (Mathews 1938). 

This is a report on behavior, however, the fields of population biology, 

physiology, ecology, and the subject of human disturbance of the whales are closely 

linked. Separating out the subject of behavior from these realms is at times difficult and 
4 

arbitrary. In addition to a description of specific behavior patterns in Hawaii, reference is 

made to migrations, local movements, habitat use, and physiological cycles. Not 

addressed are the issues of human impacts on whale behavior. 

A variety of terms to describe social groups and behavior and specific actions or 

postures developed along with the early studies. These terms vary to some extent between 

research groups within Hawaii, and between Hawaii and other regions. In Appendix 2, 

terms are melded from three Hawaiian studies: Darling 1983, Glockner-Ferrari and 

Ferrari 1985, and Gabriele 1992 (whose terms were in turn based on Bauer 1986 and 

Helweg 1989), and these are used in this report. Where postures or actions were 

correlated with gender in the earlier reports the specific source of the correlation is 

referenced. Social groups are defined in Table 1 and include references to significant 

(first or largest) data sets confirming sex composition. 
5 

Table 1. Definition, typical behavior and sex composition of humpback social units. 

Term Definition Typical Behavior Sex 

Composition 

Sex 

Reference 

Cow/calf Mother and calf of 

the year 

Pair stationary (apparently 

resting), or traveling; with calf 

beside or in contact with cow; 

often inshore of other groups; do 

not normally mix with other 

cows/calves 

Female and 

offspring 

Cow/yearling Mother and year old 

calf from previous 

year 

More common in early season, 

near weaning; many similarities to 

cow/calf behavior but more 

separation between cow and 

yearling 

Female and 

offspring 

Cow/calf/yearling Mother and calf of 

year with yearling 

still present 

Rare; combination of the above Female and 

offspring 

Subadults juveniles - from 

recently weaned 

yearling to 4-5 years 

Alone; in pair/trio with other 

juveniles; in association with 

adult male singing or in sexual 

activity; and following on 

periphery of adult groups 

Male and Female Darling 1983, 

Glockner-Ferrari 

and Ferrari 1985 

Cow/calf and escort Mother/calf and 

escorting male 

Common; males stays close to 

female; if stationary, often below; 

if traveling, just to one side; escort 

will defend position against other 

males with agonistic behavior 

Female- Male Darling 1983, 

Glockner 1983, 

Darling et al. 1983, 

Baker and Herman 

1984, Mobley and 

Herman 1985 

Singer Adult singing 

humpback song 

Usually alone; but at times paired 

with male or female, or as escort; 

may be stationary or traveling; 

generally sings for 10-15 minutes 

between brief surfacings; sings 

until interacts with other whales 

Male Winn et al. 1978, 

Darling 1983, 

Glockner-Ferrari 

and Ferrari 1985, 

Darling and Berube 

2001 

Joiner Non-singing males 

that join singer 

Approach and join a singer; 

singing- joining interchangeable 

behavior 

Male Darling 1983, 

Darling and Berube 

2001 

Lone Lone non-singing 

adult 

Usually traveling 

steadily on one direction to 

eventually join other whales 

Usually male; 

rarely female 

Darling 1983, 

Gabriele 1992 

Pair Pair of adults At least 3 common behavior 

patterns; traveling side by side 

steadily in one direction; milling 

with varied interactions including 

probable agonistic or mating; 

stationary, remaining submerged, 

close together and motionless for 

15-20+ minutes at a time 

 

Male-male 

or 

Male-female 

Darling 1983, 

Clapham et al. 

1992, Gabriele 1992 

Competitive/surface 

active group 

Larger group (3-20) 

of adults - may 

include juveniles on 

the periphery 

Group usually moving rapidly, 

often at surface and in random 

directions, includes social sounds; 

interaction predominantly 

aggressive behavior between 

males (with possible male 

coalitions at work), following the 

female; most activity by principal 

escort defending its position from 

Multiple males and 

one female; later in 

season typically 

female is cow with 

calf (exceptional, 

brief instances of 

two females) 

Darling 1983, 

Glockner-Ferrari 

and Ferrari 1985, 

Clapham et al. 1992 
6 

challengers or secondary escorts 

RESULTS 

General Behavior – The Hawaiian Breeding and Nursery Grounds 

Definition and Boundaries 

The geographic boundaries of reproductive behavior are not readily defined, as the 

activities occurring in Hawaii are apparently a continuum of behavior beginning in the 

late season feeding grounds, occurring throughout the migration, as well as in the winter 

assembly (Glockner and Venus 1983, McSweeney et al. 1989, Clapham and Mattila 1990, 

Brown and Corkeron 1995, Craig and Herman 1997). 

The Hawaiian regions utilized by the whales are well documented and have been 

consistent from the first surveys (Wolman and Jurasz 1977, Rice and Wolman 1978) to 

present (Mobley et al. 1999), shown in Figure 1. The whales are distributed throughout 

waters around the main Hawaiian Islands with highest densities on Penguin Banks and 

within the Four Island Group of Maui, Molokai, Lanai and Kahoolawe, and with lesser 

concentrations off the Kona coast, and around Kauai. 

Figure 1. Hawaiian Island humpback whale distribution, primary study sites, and Hawaiian Island 
7 

Humpback Whale National Marine Sanctuary boundaries. 

The highest densities of whales appear to correlate with shallow banks around or 

between islands. In Mobley et al.’s (1994) (cited in Frankel et al. 1995) surveys the 

majority of animals, 74% of all pods seen, were in waters less than 100 fathoms (182 m). 

However, deep inter-island channels are crossed regularly (e.g., Mate et al. 1997, Cerchio 

et al. 1998) and singing activity occurs in deeper waters surrounding the Hawaii banks 

(Frankel et al. 1995). Dive profiles indicate the humpbacks utilize the full three 

dimensions of the Hawaiian bank habitat, with both shallow as well as deep dives to 200 

feet and apparently the ocean floor (Baird et al. 2000). 

Most behavior studies have been conducted off: 1) west Maui in the Auau and 

Kalohi channels between Maui, Lanai and Molokai; 2) the Kona coast of Hawaii with 

most along the northwest Kohala coast; and 3) to a lesser degree, off the west and south 

shores of Kauai. These are all calm water lees from trade winds, and comprise a relatively 

small portion of the overall winter range (Figure 1). 

 

Local Movements and Use Patterns 

The potential circulation of all social classes of whales throughout the main 

Hawaiian Island chain, with animals not remaining in any one area for extended periods, 

appears to be the rule (e.g., Mate et al. 1997, Cerchio et al. 1998); however hypotheses of 

differential use of the region appear in the literature, and several questions remain open 

(e.g., Baker and Herman 1981, Mobley and Herman 1985, Craig and Herman 2001). 

Based on northwesterly movement of highest whale densities, there was early, 

published speculation that whales entered the Hawaiian region at the southern end of the 

Big Island, and generally moved through the region southeast to northwest, eventually 

leaving from Kauai (Baker and Herman 1981). This was subsequently shown not to be a 

strict rule, with records of short-term movements of individually identified whales 

moving in the reverse direction from Maui to Hawaii (Darling and McSweeney 1985), 

Kauai to Hawaii (Cerchio et al. 1998), and satellite tagged whales moving seemingly at 

random throughout the islands (Mate et al. 1997). 

Cerchio et al. (1998) reported 15 within one season resightings between Hawaii 

and Kauai with nine whales moving from Hawaii to Kauai and six moving the reverse 

direction, and concluded there was no directional trend between the islands. The shortest 

inter-island movement time was eight days. They suggested that males were significantly 

over represented in inter-island matches, and that animals actively engaged in courtship 

behaviors might be more wide ranging than others. The notion of free circulation, nonunidirectional movement around the islands was emphasized by a whale satellite-tagged 

by Mate et al. (1997) which, in 9.9 days, traveled at least 820 km (mean 80 km /day) 

through the coastal waters of five of the Hawaiian Islands: Kauai, Oahu, Molokai, 

Penquin Banks and the Kalohi Channel between Molokai, Maui and Lanai. These authors 
8 

also note that Kauai may be a northward migration departure point, and hence there 

remains some speculation that general abundance may shift northward as the season 

progresses (Mate et al. 1997). 

The picture emerging is one of no social/behavioral boundaries within the main 

Hawaiian Islands, and high mobility throughout the islands by all social groups – possibly 

some more that others. However, speculation of differentiated use patterns of the overall 

area persists. Baker and Herman’s (1981) suggestion of some degree of segregation 

between whales wintering off different islands, appears not to be the case. However, there 

are hints that behavior patterns and social groups may vary to some degree between some 

locations; these may be due to whale density differences rather than habitat or geographic 

preferences by specific whales (Mobley and Herman 1985, Smultea 1994, Frankel et al. 

1995). Recently, Craig and Herman (2000) speculated that female distribution in 

Hawaiian waters may depend on reproductive status, with females more likely to be 

accompanied by calves off Maui than off the Hawaii. Overall, the question of whether 

predominant adult social groups and behavior patterns vary between locations within the 

main Hawaiian Islands remains open. 

The clearest case of habitat preference is that cows with young calves are 

consistently found in shallower, more inshore waters than the majority of the population 

(e.g., Glockner-Ferrari and Ferrari 1985, Smultea 1994). However, attempts to define 

specific nursery areas or conditions have been confounded by the fact that cows with 

young calves are by no means confined to shallow waters or to one region within the 

islands. Cow/calf movement throughout the island chain occurs (Craig and Herman 1997, 

B. Mate pers. comm. 2001), and they are regularly sighted on Penguin Banks, some of the 

roughest offshore water in the area (Mobley et al. 1999, B. Mate pers. comm. 2001). 

Presence and Individual Length of Stay 

Humpback whales are abundant in Hawaii from mid-December through early 

April, with peak numbers in February and March (e.g., Herman and Antinoja 1977, 

Mobley et al. 1999). However, whales are regularly seen from November through May, 

and sightings have occurred as late as the end of June and as early as September 

(Glockner-Ferrari and Ferrari 1985, M. Jones pers. comm. 2001). Thus humpback whales 

may utilize Hawaiian waters during ten months of the year. 

A figurative bell-shaped abundance curve of humpbacks in Hawaii, as shown in 

Figure 2, correlates with a variety of behavior studies. For example, Thompson and Friedl 

(1982) had song detections as early as November and as late as June which peaked 

between February and May. Au et al. (2000) noted the peak of singing activity was end of 

February to mid-March. Other studies indicate that the degree of transience in groups 

(Mobley and Herman 1985), amount of aggressive activity (Baker and Herman 1984) and 

number of competitive/mating groups (Darling 1983) all appear to have similar 

occurrence and peak times related directly to the density of whales in the area. 
9 

Figure 2. Timing of humpback whale social and behavioral events in Hawaii – figurative summary (after 

Thompson and Friedl 1982, Darling 1983, Baker and Herman 1984, Mobley and Herman 1985, Gabriele 

1992, Mobley et al. 1999, Au et al. 2000). 

The arrival and departure of whales in Hawaii is likely segregated to some degree 

by age, sex and reproductive condition. Studies based on whaled specimens indicate 

migratory order as follows: first in the procession are females with a yearling; followed 

by immature independent whales, resting females (whose ovaries and mammary glands 

showed no evidence of recent activity) and mature males; and finally females in late 

pregnancy. The departing migration is in the same order: mature females unaccompanied 

by calf (either newly pregnant or resting); then immature whales; mature males; and 

finally new mothers (Chittleborough 1958, 1965; Nishiwaki 1959, 1966; Dawbin 1966). 

This order appears corroborated to some extent by observations in Hawaii: juveniles are 

common early in the season; adult pairs (presumably male-female) without calf common 

in January and early February; the increase in numbers of cows with calves after February 

1 and through March; and cows with newborn the last to depart (e.g., Baker and Herman 

1981, Darling 1983, Glockner-Ferrari and Ferrari 1985, Mobley and Herman 1985, 

Gabriele 1992). At the peak of the season all age/sex/reproductive categories are present. 

It is apparent that some portion of mature females do not make the entire 

migration each year, presumably due to high energy costs of migration and reproduction 

(Lockyer 1981). There is an ongoing discussion in the literature of the females “missing” 

from the breeding grounds, and it is generally agreed that far more males than females 

make the migrations (Chittleborough 1965, Dawbin 1966, Brown et al. 1995, Craig and 
10 

Herman 1997). Brown et al. (1995) noted a ratio of 2.4:1 males to females on the 

migration past East Australia. Craig and Herman (1997) assert that individual males 

undertake the migration to Hawaii more often than individual females, and suggest this is 

due to females taking a “resting year”, and some females becoming pregnant enroute and 

returning to the feeding grounds. However, this question remains open as, for example, 

limited Alaska data on over-wintering whales does not indicate a preponderance of 

females (Straley 1999). 

There are suggestions that most individual whales do not spend the whole season 

in Hawaii, and in fact are present for short periods relative to the overall humpback 

season. Darling (1983), from the results of a study from 1977-81 with 1,553 

identifications of 922 individuals and 631 repeat sightings, reported that although whales 

were present over five months or more, 88 % of repeat sightings of individuals were 

within six weeks, and the majority two weeks. Although this is not conclusive due to the 

small study area in relation to the size of the Hawaiian range, it is highly suggestive. The 

construct is that individuals arrive, spend a period of several weeks in Hawaii then leave, 

just as other individuals arrive and so on. 

The exception to this pattern appears to be that some males spend a significantly 

longer time in the region. In Darling’s (1983) data all 17 whales of known sex recorded 

over a six week period were males. Whereas the longest reported repeat sightings of 

females have been: 39 days (two different cows with calves) (Darling 1983), 37 days 

(Mobley and Herman 1985), 48 days (Glockner and Venus 1983), and four-five weeks 

(Gabriele 1992), the longest repeat sightings of individual males have been 91 days (13 

weeks) (Darling 1983) and eight-nine weeks (Gabriele 1992). This suggests that some 

males may be present from mid-Jan to mid April or essentially the entire peak season. 

Further, several examples suggest that some specific individuals stayed for a long period 

from year to year (Darling 1983). These longer term repeat sightings of males combined 

with a Darling and Morowitz (1984) theoretical calculation that suggests a small subpopulation of whales (presumably these males) remain a longer period than average, led 

to speculation that these may be mature and perhaps dominant males that are maximizing 

mating opportunities. This has not been proven. 

Reproductive Cycles 

One key to humpback whale behavior patterns in Hawaii is the female 

reproductive cycle, particularly timing, recurrence and duration of estrus, and factors 

which may influence these in the short-term. Male mating strategies and behavior directly 

result from the distribution of estrus females in time and space, which in turn are 

governed by broader ecological factors (Emlen and Oring 1977). Our understanding of 

the humpback female reproductive cycle has developed from: 1) the examination of 

ovaries of a series of whaled specimens (Mathews 1938; Nishiwaki 1959, 1960, 1962; 

Chittleborough 1965; Dawbin 1966; Tomlin 1967); 2) birth histories of individual 
11 

females (Glockner-Ferrari and Ferrari 1985, Baker et al. 1987, Clapham and Mayo 1987, 

Straley et al. 1994); and 3) circumstantial evidence from male behavior patterns (e.g., 

Darling 1983, Baker and Herman 1984). Reproductive cycle information is summarized 

in Table 2, as it sets the context for much of the behavior in Hawaii. 

Table 2. Reproductive cycle summary. 

Age of maturity 4-6 years

Birth rate Variable: average one calf every 2-3 years; annual birth potential 

Gestation 11-11.5 months

Lactation 10 months

Timing of estrus Peak 3-5 winter months; exceptions may occur throughout year

Timing of spermatogenesis Peak during winter months

Recurrence of estrus Seasonally polyestrus (if pregnancy does not result)

Duration of estrus Unknown - one circumstantial observation of at least 6 days (Darling 1983)

Postpartum estrus Common, but percentage of successful conceptions unclear 

Operational sex ratio 2-3 males to 1 female

Sexual Maturity and Birth Rate 

Most female humpback whales reach sexual maturity mean age of four-five years 

indicated by whaling studies (Chittleborough 1959, 1960, 1965; Nishiwaki 1959), and 

observations of two females of known age in the North Atlantic that attained sexual 

maturity at four and six years (Clapham and Mayo 1987). However, there is only limited 

information from the North Pacific, and early data from Alaska suggests that reproductive 

age may be eight or more years (Gabriele pers. comm. 2001). Thereafter, the average 

birth rate is every two to three years (2.38: Barlow and Clapham 1996 in North Atlantic, 

2.26: Straley et al. 1994 from Alaska), however, there is significant variability in this 

cycle, and clear evidence of an annual birth potential (Mathews 1938, Chittleborough 

1958, Darling 1983, Glockner and Venus 1983, Glockner-Ferrari and Ferrari 1985, Baker 

et al. 1987, Straley et al. 1994, Barlow and Clapham 1996). One of the most cited 

examples is a known cow that had four calves in four years and seven in 11 years 

(Glockner-Ferrari and Ferrari 1995). Straley et al. (1994) reports five females from 

Alaska that demonstrated successful annual reproduction. 

Researchers have puzzled over the annual birth rate. On one hand, examination of 

ovaries of whaled animals suggests that only a small portion (one estimate in 

Chittleborough 1958: 8.5%) of females overall conceive annually, which, considering the 

significant energetic costs of simultaneous lactation and gestation seems logical. On the 

other hand, the near universal behavior of males accompanying and competing over cows 

with newborn calves (e.g., male escorts found in over 80% of cow calf encounters by 

Glockner-Ferrari and Ferrari 1985), backed up by the annual birth rate histories, strongly 

suggests a post-partum estrus is a common occurrence. This apparent incongruity may be 

explained by a significant difference between the numbers of postpartum ovulations 

versus successful postpartum conceptions referred to by the whaling data (GlocknerFerrari and Ferrari 1985, Mobley and Herman 1985). Gabriele (1992) suggests that most 
12 

escorting of females with calves occurs after the other single (more reproductively 

promising) females leave Hawaii. Straley et al. (1994) suggests that that postpartum 

ovulation is a common event in female humpback whales, but that only a proportion of 

ovulating females can maintain pregnancies, dependent on the individual’s current 

condition. 

 

Timing, Recurrence and Duration of Estrus 

Studies based on examination of a large series of specimens indicate humpback 

whales generally undergo a seasonal sexual cycle with its peak during three-five winter 

months (Mathews 1938; Nishiwaki 1959, 1960, 1962; Chittleborough 1965, Dawbin 

1966). In the North Pacific, Nishiwaki (1959, 1960, 1962) determined the peak of 

ovulation occurs from the end of January to the end of February in western Pacific, 

Ryukyuan waters, coinciding well with the peak abundance and activity in Hawaii. To 

complicate this view however, some reports, also based on examination of ovaries, 

indicate successful pregnancies can occur well out of synchronization with the majority 

(Mathews 1938, Chittleborough 1954, Tomlin 1967). Tomlin (1967), by examining 

humpback fetuses in the North Pacific, suggested that successful mating can occur in 11 

or 12 months of the year, with two apparent peaks, one in Feb-April and the other in 

September. 

Mathews (1938) and Chittleborough (1965) conclude that females humpback are 

seasonally polyestrus. Mathews (1938) states that females frequently to not become 

pregnant at first ovulation of the sexual cycle and may experience several cycles before 

pregnancy occurs. Chittleborough (1965) suggests that there may be several sexual cycles 

terminating when conception is successful or when they migrate to feeding grounds. The 

duration of a particular estrus cycle is not known. Darling (1983) reports an observation 

of the same female leading competitive groups of males on both 1 and 6 February 1980, 

and this may indicate an estrus cycle extended over that time period. 

The only direct insight into timing and duration of estrus for humpbacks in 

Hawaiian waters, and confirmation of whaling data now 40+ years old, are behavioral 

observations of extreme male interest in, and competition over, females. This behavior is 

mostly likely the result of female estrus. Darling (1983) plotted sightings of different 

male/female groups over five seasons, 1977-81, clumped into one-week periods 

represented in Figure 2. Presuming that male attention of a female in indicative, estrus 

occurred over at least six months from December to May, with the majority from midJanuary to mid-April. A peak of multiple male (presumably single female) competitive 

groups without calves occurred through February and March, several weeks earlier than 

multiple males following females with calves, apparently undergoing postpartum estrus. 

Gabriele (1992) presents complimentary data, with the occurrence of male-female groups 

peaking 9 February to 19 March, followed by male-mother/calf groups peaking 19 

February to 1 April, and notes the overlap from 19 February to 19 March when the most 

estrus females per male are present, with the lowest operational sex ratio. Overall this 
13 

correlates well with peak pod membership changes (Mobley and Herman 1985), 

aggressive encounters (Baker and Herman 1984), and singing activity (Au et al. 2000). 

And, as noted by Au et al. (2000), this behavioral information correlates well with peak 

ovulations estimated by whaling data. 

Humpback social and behavioral patterns are closely linked to the female 

reproductive cycle. For example, with a sex ratio at birth of 50:50 (Chittleborough 1954, 

Glockner-Ferrari and Ferrari 1990), and if the majority of females follow a two or three 

year birth cycle, then there are many more sexually mature males than fertilizable females 

in any one season. This leads to increased competition between males (Emlen and Oring 

1977, Gabriele 1992). The fact that females come into estrus over a five month (or 

longer) period suggests that males develop mating strategies over extended time periods, 

to “be there” for the next wave of females. Due to postpartum ovulation, males seek out 

and compete for access to estrus females with newborn calves, with potentially negative 

impacts on the calf (Cartwright 1999). Also, subclasses of recently weaned yearlings and 

juveniles less than four or five years old are likely to be engaged in different behavior 

patterns than the mature animals. 

Mating Behavior 

There remains no documented observation of humpback whale copulation in 

Hawaiian waters, yet the circumstantial evidence is sufficient to presume that it occurs. 

However, this leaves us guessing when and in which behavior pattern or social group 

mating actually occurs, what behavior precedes or follows, or if an individual animal 

mates once or many times during the season. This makes any discussion of mating 

behavior somewhat speculative. 

Mammalian mating systems are generally divided into two broad categories: 

monogamous and polygamous. The former implies that a male and female form a pair 

bond and only mate with each other; the latter implies that individuals have multiple 

mating partners. Observations strongly suggest there is no permanent pair bond formed 

between specific male and female humpbacks, therefore monogamy is ruled out as the 

mating system. This contradicts Wilson’s (1975) categorization of humpbacks in his 

overview of social organization, where he suggests they form family groups (this mistake 

was apparently the result of anecdotes from Slijper 1962). 

There is general agreement that humpbacks, like most mammal species, are 

polygamous (Herman and Tavolga 1980, Baker and Herman 1984). More specifically, 

humpbacks are likely either polygynous, implying that a male monopolizes and mates 

with several females, or promiscuous where no apparent monopolizing of females occurs 

and both males and females mate several times with different individuals (Darling 1983; 

Mobley and Herman 1985; Clapham 1993, 1996; Gabriele 1992; Brown and Corkeron 

1995). These suppositions are based on behavioral observations including: 1) short-term 

associations of males with different females (e.g., Darling 1983, Mobley and Herman 
14 

1985); 2) multiple males competing through overt fighting for access to single females 

(e.g., Tyack and Whitehead 1983, Baker and Herman 1984); 3) a male-biased operational 

sex ratio, i.e., a high ratio of sexually active males to fertilizable females (e.g., Emlen and 

Oring 1977, Gabriele 1992); and 4) male-male interactions involving the song (Darling 

1983, Darling and Berube 2001). 

The question of whether humpbacks are polygynous or promiscuous is significant 

and, apparently, remains open. Baker and Herman (1984) suggested they are 

promiscuous, with females associated serially and simultaneously with multiple males, 

and males associated serially with multiple females. Gabriele (1992) notes it seems 

doubtful that a single male could monopolize a female and prevent other males from 

mating with her. On the other hand, Brown and Corkeron (1995) point out that 

characteristically, in promiscuous systems: 1) males compete primarily through sperm 

competition; 2) behavior is characterized by male-male interactions that are not highly 

aggressive; and 3) males have relatively large testes and penises (as in gray and right 

whales). They note this description does not fit humpback whales, known for their 

striking male-male agonistic interactions around females, and relatively small testes and 

penises (Brownell and Ralls 1986). Thus Brown and Corkeron (1995) argue that it would 

seem unlikely that males would physically compete for access to a female, only to then 

engage in sperm competition as promiscuity suggests. 

The key question to further understanding humpback behavior on the breeding 

ground is whether or not males attempt to monopolize females with strategies such as 

formations of territories, harems or dominance hierarchies common in land mammal 

mating systems. At this time, observations of individual behavior and mating success are 

not detailed enough to warrant conclusion on this question. However, several hypotheses 

have emerged and are summarized in Table 3. 
15 

Table 3. Mating system hypotheses. 

Mating System Characteristics Accounts For Problems 

Dominance Polygyny Males determine 

beforehand through 

displays and fights an 

order that determines 

which has priority 

access to estrus females; 

individuals must 

remember outcomes of 

previous encounters; 

relatively few dominant 

animals obtain most 

matings 

Variable male-male 

interactions facilitated 

by song ranging from 

brief non-agonistic to 

agonistic; variable male 

competition over 

females; seems a 

functional system for 

estrus over 3-5 months 

No conclusive 

documentation of 

dominance sorting; or 

proof of variable mating 

success; some say that 

male movements and 

impermanence of 

affiliations give this no 

time to develop or have 

utility (Frankel et al. 

1995) 

Lek Polygyny Males assemble in 

mating area generally 

establishing display 

territories; offer no 

resources other than 

genes; display to 

females, offering 

opportunities for 

females to select mates; 

usually just a few males 

obtain most matings 

Multiple males 

seasonally assembled; 

no resources other than 

genes; displaying 

through song (presumed 

directed at females as 

well as males) 

No establishment of 

male spatial structuring, 

i.e., territories (although 

floating territories have 

been proposed Clapham 

1996); no evidence that 

the song is directed at or 

attracts females 

Male Cooperation Males form coalitions to 

assist each other in 

obtaining matings (Note: 

this behavior could 

evolve in several 

different mating systems 

for non-dominant males) 

Several observations of 

non-agonistic and/or 

apparently cooperative 

male unions in relation 

to estrus females; 

apparently used by other 

cetaceans 

Rare among non-related 

males, hence with 

theoretical challenges 

The hypotheses of dominance polygyny (e.g., Darling 1983, Mobley and Herman 

1985, Clapham 1992, Brown and Cockeron 1995, Darling and Berube 2001) and lek 

formation (e.g., Herman and Tavolga 1980, Whitehead and Moore 1982, Mobley and 

Herman 1985, Clapham 1996, Cerchio 1996) have received about equal attention in the 

literature. The former predicts the development and maintenance of a male hierarchy for 

access to estrus females by fighting and display – potentially with the song the male-male 

display; the latter predicts males create territories (perhaps “floating,” see Clapham 1996) 

and the song functions as a display to attract females to the most “fit” male. As Table 3 

indicates both hypotheses account for some observations but both have detracting aspects, 

and neither has been tested conclusively. 

A further emerging hypothesis suggests that some males may cooperate and even 

form coalitions to optimize mating opportunities. This idea is based on a few 
16 

observations of the apparent coordination or cooperation of some males in gaining access 

to a female in competitive groups in the West Indies (Clapham 1992 et al.), Australia 

(Brown and Corkeron 1995) and Hawaii (Darling and Berube 2001), and the speculation 

by the latter authors that such organization of males may be facilitated by the song. This 

is a substantially different view of the mating system, and may dominate discussion over 

the next few years. 

All of these ideas remain highly speculative, and are very likely to be modified 

with further research. Ultimately, only genetic studies that deduce paternity and 

differential mating success of males will illuminate the mating system of humpback 

whales. Such studies are underway in the Socorro, Mexico breeding area (S. Cerchio pers. 

comm. 2001). 

Male Behavior Patterns 

Male humpbacks in Hawaii are found in lone behavior, in male-male associations 

and interactions, and in male-female associations and interactions. Male behavior patterns 

are: 1) singing; 2) interacting with singers or non-singing males – at times forming all 

male pairs, trios or larger groups; 3) escorting or guarding adult females; 4) defending, or 

challenging, the escort position with aggressive behavior; and 5) presumably mating. 

Most male behavior patterns, interactions and associations are short-lived, lasting 

only minutes to hours, with the animals apparently orienting to any female in estrus 

while, reportedly, either avoiding each other (Tyack 1981,1983; Frankel et al. 1995), or 

involved in agonistic interactions (Tyack 1981, 1983; Tyack and Whitehead 1981; 

Darling 1983; Baker and Herman 1984; Mobley and Herman 1985). Male-female pairs 

(with or without calf) are the most stable groups lasting as much as a day or more 

(Darling 1983, Baker and Herman 1984, Glockner-Ferrari and Ferrari 1985, Mobley and 

Herman 1985, Gabriele 1992). Baker and Herman (1984) report one cow/yearling group 

that was escorted by the same male over two days. More recent studies have raised the 

possibility that some males may also form temporary non-agonistic or even cooperative 

unions (Clapham 1996, Brown and Cockeron 1995, Darling and Berube 2001). 

 

Several researchers have speculated that males have two strategies to gain access 

to females: 1) singing to advertise to and/or attract them, and 2) fighting in competitive 

groups to gain access to them. It has been suggested that they alternate between these 

strategies (Tyack and Whitehead 1983, Frankel et al. 1995, Au et al. 2000). Although this 

speculation recurs in the literature, as discussed below, it is not proven and is being 

questioned by ongoing research. 

Singing 
17 

Male humpback whales emit a complex series of loud sounds over and over 

known as their song (Payne and McVay 1971, Winn et al. 1973, Darling 1983, Glockner 

1983, Darling and Berube 2001). Singing peaks strongly during the breeding season, but 

occurs during migrations to the breeding area and in late summer feeding grounds (Payne 

and McVay 1971, Winn and Winn 1978, Mattila et al. 1987, McSweeney et al. 1989, 

Clapham and Mattila 1990, Brown and Corkeron 1995, Au et al. 2000, C. Gabriele pers. 

comm. 2001). Singing is a ubiquitous feature of the breeding grounds, collectively 

introducing substantial noise into the environment (Au et al. 2000). Au et al. (2000) 

reports from studies off west Maui, that singing increased significantly at night, but note 

that Helweg and Herman (1994), recording off Kauai under different conditions and 

methodology, report no such diel rhythm. 

Singers are most often lone adult whales, but may, in a minority of encounters, 

have an adult companion that is either male or female (at times with calf; that is, the 

escort is singing) (Darling 1983, Darling et al. 1983, Baker and Herman 1984, GlocknerFerrari and Ferrari 1985, Frankel et al. 1995, Darling and Berube 2001). There have been 

a few observations of smaller, juvenile whales near a singer (Darling 1983, GlocknerFerrari and Ferrari 1985). Singers may be stationary (or nearly so), with the tail 

approximately 7-15 m below the surface in a head down tail up posture as in Figure 3; or 

they may be traveling while singing (Tyack 1981, Darling 1983, Frankel et al. 1995, 

Darling and Berube 2001). It is not known at what age males begin singing, but the 

presumption is that it is related to sexual maturity (five to seven years). Glockner-Ferrari 

and Ferrari (1990) report one whale known to be ten years old that was observed singing. 

Singing typically continues until the singer is either: 1) joined by other whale(s), 

usually a lone adult but occasionally a pair; or 2) the singer stops and swims off to join 

group that includes a female – either a competitive group composed of a female and 

several males, or cow/calf and escort thereby creating a competitive group (Tyack 1981, 

Darling 1983, Darling and Berube 2001). These interactions may occur after a singer has 

been singing for a few minutes or after many hours, this very likely dependent on density 

of whales and time of season. In the former case the pair most often split-up again quickly 

and travel in different directions, with often one or the other participant eventually 

beginning singing again. When a singer moves off to join a competitive group, 

documented as far away as 9 km distant (Tyack and Whitehead 1983), it is apparently 

attracted by the social sounds made in the group (Tyack 1983, Silber 1986, Mobley et al. 

1988). 
18 

Figure 3. Singer. A common posture for a singer off Maui is motionless, head down and tail up with the 

fluke 7-15 m below the surface. Whales may also sing when they are traveling. 

The song

The song varies from five-20 minutes in length. It has a hierarchical structure 

consisting of several different single sounds or “units” that compose a “phrase,” which is 

then repeated a number of times in a “theme.” Several different themes, often four to six, 

composed of different phrases, make up the song. The song is a continuous loop in that 

singers sing Themes 1, 2, 3, 4, 5, 6, then begin again at 1 and so on. The song session can 

continue for hours (Payne and McVay 1971). The most unique characteristic of the song 

is that it changes gradually in composition as it is being sung, but there is a tendency for 

all the whales in a population – which may range over ocean basins – to change 

collectively and sing essentially the same version at any one time (Winn et al. 1981, 

Payne et al. 1983, Payne and Guinee 1983, Cerchio et al. 2001). Humpback songs studied 

in Bermuda and Hawaii changed gradually, in a sense predictably, with the entire 

composition “turning over” in 4-5 years (Payne et al.1983, Payne and Payne 1985); but a 

recent study off eastern Australia showed potential for quicker change, with the whales 

adopting a song from western Australia in its entirety over just a two year period (Noad et 

al. 2000). 

The function of the song has been, and continues to be, subject to much 

speculation. The speculation that has received the most discussion is that it is a sexual 

display by males to attract females and/or detract males (Winn and Winn 1978, Tyack 
19 

1981, Tyack and Whitehead 1983, Baker and Herman 1984, Helweg et al. 1992, Frankel 

et al. 1995 Clapham 1996, Au et al.2000). In this vein, Frankel et al. (1995) suggest the 

song is a male spacing mechanism. Within the idea that the song attracts females to the 

singer are the suggestions that it may provide some indication of fitness of the singer to 

the female (Chu and Harcout 1986, Chu 1988, Helweg et al. 1992), or that it attracts 

females in a lek mating system (Herman and Tavolga 1980, Mobley and Herman 1985, 

Clapham 1996). Alternatively, it has been proposed that the song is primarily a display 

between males, signaling status (Darling 1983), or otherwise involved in male social 

ordering (Darling and Berube 2001). Other proposed speculative functions of song 

include promoting synchrony of estrus in females (Baker and Herman 1984), a migratory 

beacon (Clapham and Mattila 1990), or sonar to locate females (Frazer and Mercado 

2000). 

Interactions with singers 

Interacting with singers is a male behavior pattern. This may be the single most 

confusing topic in the humpback behavior literature. Substantial momentum has built up 

over 25 years of literature for the notion that males avoid singers, males invariably fight 

when in close proximity and the song serves to attract females for mating purposes 

(Tyack 1981, 1983; Tyack and Whitehead 1983; Baker and Herman 1984; Helweg et al. 

1992; Frankel et al. 1995; Clapham 1996). Yet, there is increasing evidence that brief 

non-agonistic interactions between males are a common recurring pattern on the breeding 

grounds, and observations of females joining singers are extremely limited (Darling 1983, 

Brown and Corkeron 1995, Clapham 1996, Darling and Berube 2001). 

The speculation that the function of the song was to attract females apparently 

arose in Winn and Winn (1978). Tyack (1981, 1983) concluded, with one example of a 

cow/calf joining a singer and playback experiments, that females joined singers, nonsingers had a tendency to avoid singers, and the song signals male preparedness to fight. 

These views were tempered somewhat by Mobley et al. (1988) who reported playback 

experiments that indicated the song did not serve as an attractant for females, as measured 

by direct approach, although they suggest it may still serve as a basis for female choice. 

Helweg et al. (1992) proposed the song had two messages: for males to stay away and for 

females to join. Also, Frankel et al. (1995) suggest that, with 58 singers used in spatial 

analysis and the average distance between singers was 9.4 km, the song may serve to 

create and maintain distance between singers and between singers and other males. These 

authors also suggested that the song involves males advertizing the message to other 

singers to stay away, and otherwise may function as a basis for female choice. 

In contrast, Darling and Berube (2001) report that lone males commonly join 

singers (76% or 32 of 42 observations) as illustrated in Figure 4, leading to brief 

interactions or longer term male groups. Of 22 lone whales that joined singers whose sex 

was determined, all were males. The joining or interacting male may approach slowly, 

circling several hundred meters away for a period of time, or may approach directly – like 
20 

a torpedo shooting under boat – and join the male singer. Singing usually, but not 

necessarily, stops with the joining. The interactions that occur vary from a close approach 

and departure with the two never surfacing together; to a brief simultaneous surfacing 

within a whale length from each other and splitting, to longer interactions that may 

include surface behavior, tail lobs, tail throws, breaches and flippering by one or both of 

the whales. In one in five such interactions the males did not split-up immediately and 

this led to pair or larger group formation (possibly related to dominance sorting or 

coalition formation), and in one case such a group joined a competitive group. Darling 

and Berube (2001) note that the wide range of behavior subsequent to joining, ranging 

from passive to agonistic, splitting to group formation, suggests a range of social 

relationships between the males. Thus, it appears the song facilitates interactions between 

males, the majority of which appear to be non-agonistic. 

Figure 4. Singer and joiner. A singer is joined by a lone adult male. The singing usually stops when this 

occurs, and interaction is typically brief followed by a split. At times this interaction leads to formation of a 

male-male group. 

Presuming all these observations are accurate, the best summary is that some 

males and some singers maintain distance from singers (Tyack 1981, 1983; Frankel et al. 

1995), whereas others approach, join and interact with singers on regular basis (Darling 

and Berube 2001). This variability, or differential behavior of specific males towards each 

other, may be significant in terms of social organization. There remains extremely limited 

evidence that females are attracted to singers, but it is too early to rule out that some, as 

yet undiscovered, female-initiated interaction with singers occurs. 
21 

Escorting/Guarding a female 

A common adult male behavior pattern on the breeding grounds is to pair with or 

“escort” a female; this is most readily recognized when the female has a calf, as shown in 

Figure 5. As many as 86% of cows with calves encountered in a season have been 

accompanied by an escort (Glockner-Ferrari 1985), and this is the most stable of known 

humpback social groups (beyond cow/calf) which may last for hours to days (Baker and 

Herman 1984, Mobley and Herman 1985). Stable pairs of adults, a predominant adult 

social group in January-February are likely often males “escorting” females without calf 

(Gabriele 1992). Although there was very early published speculation otherwise, there is 

now universal agreement that escorting is a male behavior pattern (Darling 1983, Darling 

et al.1983, Glockner 1983, Glockner and Venus 1983, Mobley and Herman 1985, 

Clapham et al. 1992). 

Figure 5. Cow/calf and escort (aerial view). Females with young calves are commonly escorted by an adult 

male. This is one of the more stable social groups on the breeding grounds. 

The escort male essentially “sticks” to the female. If the female is settled and 

resting, so is the escort; if traveling, the escort is usually within a whale length and within 

sight of the female. The escorts breathing and dive patterns generally follow those of the 

female. In a typical resting escort-female group where the cow is motionless, the escort 

will position itself just off to one side or below, also motionless. Escort males have been 

observed singing (Tyack 1981, Darling 1983, Darling et al. 1983, Glockner 1983, Frankel 

et al. 1995). A singing escort will surface in song themes it usually does not surface in, in 

order to follow the female, emphasizing its awareness of her location and behavior (JDD 

unpublished data). 

Escorts are commonly joined by other male(s), whereby they become markedly 

agitated and this is usually followed by a variety of apparent agonistic behavior patterns. 

Generally the female and calf move during this male-male interaction with the escort 

attempting to maintain its position and, apparently, defend it against the challenger. This 
22 

interaction often melds into the typical active or competitive group described below 

(Tyack 1981, Tyack and Whitehead 1983, Darling et al. 1983, Baker and Herman 1984). 

An escort (often termed the principal escort when several males are present) may be 

displaced by other males; this observed both directly during competitive group 

interactions, and indirectly through short-term resightings of the cow and calf with 

different escorts. (Darling 1983, Tyack and Whitehead 1983, Baker and Herman 1984, 

Glockner-Ferrari and Ferrari 1985, Mobley and Herman 1985). 

Several early published reports suggested the escort, then presumed female, 

played an allomaternal role in protecting the calf (Herman and Antinoja 1977, Herman 

and Tavolga 1980), however this is not the case. Even after determination that escorts 

were males there was speculation that they played a protective role to mother and calf. 

This was partially due to Chittleborough’s (1953) description of a humpback escort 

defending a mother and calf in conflict with killer whales. Some observers interpreted the 

typical wariness of escorts to intruders, both whale and human alike, as protective of the 

cow/calf (Herman and Antinoja 1977, Glockner and Venus 1983). 

Darling et al. (1983) suggested the escorts were primarily interested in mating 

with the female, and any defense behavior was to maintain its own position rather than 

protect cow and calf. Glockner and Venus (1983) agreed that a role of the escort was to 

mate with the female and noted one cow that had a calf four years in succession, was 

accompanied by an escort on each of seven sightings during the four years she was 

observed. Mobley and Herman (1985) suggested the escort affiliates with the cow long 

enough to: 1) detect if ovulating post-partum and if so remains there; 2) detect if nonovulating and moves on; 3) detect if mated, and perhaps make an additional attempt; and 

4) possibly guard against further mating, i.e., the duration of the affiliation may extend 

beyond courtship and mating if the male engages in post-copulatory “guarding” behavior 

against other males mating with the female. 

Competitive/Agonistic behavior 

Males clearly compete and fight with each other, most commonly over immediate 

access to a female (e.g., Darling 1983, Darling et al. 1983, Tyack and Whitehead 1983, 

Baker and Herman 1984, Glockner-Ferrari and Ferrari 1985, Clapham et al. 1992); but 

apparent agonistic behavior may also occur without a female present (Tyack 1981, Baker 

and Herman 1984, Clapham et al.1992, Darling and Berube 2001). 

Displays and fights. Humpback whale agonistic behavior ranges from a variety of 

displays with no physical contact, to chases and blocking maneuvers, to physical contact 

including collisions and tail lashes or slaps to head and body resulting in bleeding wounds 

of head knobs, dorsal and tail (Darling 1983, Darling et al.1983, Tyack and Whitehead 

1983, Baker and Herman 1984, Glockner-Ferrari and Ferrari 1985, Silber 1986). In one 

case in Maui a male died in one of these groups but no necropsy was performed to 

establish the cause of death (Pack et al. 1998). 
23 

There appear to be two general, but overlapping, types or degrees of combative 

behavior in these groups, with examples shown in Figure 6 and Appendix 2. There are 

non-contact behavior patterns including bubble-streaming; underwater blows; a posture 

with back arched and head above the surface (head lift); gulping air at the surface, 

resulting in extended throat pleats, and then releasing the air underwater; lunging and/or 

slapping the chin on the surface; clapping the jaws open and shut; and directing a tail lash 

at another animal without hitting it. These could be interpreted at displays of ferocity 

and/or preparedness to fight. These behavior patterns meld into blocking and chasing, 

which in turn lead to physical contact. All can occur at the same time in one group. 

Contact includes fierce collisions; tail lashes, including beating another animal’s head 

with the tail; and rear body throws. These are violent, aggressive interactions (Darling 

1983, Tyack and Whitehead 1983, Baker and Herman 1984, Silber 1986). 

Figure 6. Examples of male agonistic displays. From left to right: 1) bubblestream - whale releases long 

streams of bubbles from its blowhole; 2) head lift - whale arches its back and swims with head out of the 

water, often gulping air and expanding throat; 3) rear body throw - whale throws its rear body out of the 

water (photos. J. Darling). 

The whale’s weapons are the tail, the whole body, and possibly the head. In one 

observation a whale turned head down and hit another whale on the tail stock with its 

head knobs. Fresh blood was noticed on the tail stock of the recipient. The combatants 

received apparently minor wounds consisting of bloody head knobs, dorsals and tail 

stocks. Some of the scars and scratches which are abundant on some whales, particularly 

males, may result from these encounters (Darling 1983, Baker and Herman 1984). 

Competition for females. Competitive or “surface active” groups are the most 

striking of humpback behavior patterns on the breeding grounds, characterized by fast 

traveling whales and high-energy surface activity. These are composed of multiple males 

(two to 20), apparently competing for access to a female presumably in estrus, as shown 

in Figure 7 (Darling 1983, Darling et al. 1983, Tyack and Whitehead 1983, Baker and 

Herman 1984, Glockner-Ferrari and Ferrari 1985, Clapham et al.1992). It is not known if 

mating occurs in these groups, but seems a possibility as extended penises, and close 

rolling and contact have been observed (Darling 1983). On the other hand the movement 

of these groups is very fast, leading some to doubt mating can occur (C. Gabriele pers. 

comm. 2001). 
24 

Figure 7. Competitive group. Group of males following and competing for access to the single female (with 

calf). 

Competitive groups are typically composed of a female (with or without calf), 

termed the nuclear animal by some authors, usually in the lead but at times in the center 

of multiple males (Darling 1983, Tyack and Whitehead 1983, Baker and Herman 1984, 

Clapham et al. 1992). There are several reported cases of two females present with 

multiple males but these appear to be exceptional (Glockner-Ferrari and Ferrari 1985, 

Clapham et al. 1992). The nearest whale to the female, the principal escort, is invariably 

the most agitated and active, clearly defending its position with bubble streams, high 

speed chases and blocks of incoming whales (Darling 1983, Tyack and Whitehead 1983, 

Baker and Herman 1984, Silber 1986). These groups are characterized by bursts of speed 

and changes in direction as the other whales, termed secondary escorts or challengers, 

apparently attempt to outmaneuver the principal escort, presumably to gain access to the 

female. Most of the interaction occurs with the principal escort and one or two of the 

challengers, with other animals following along on the periphery and apparently less 

involved. Tyack and Whitehead (1983) reported that occasionally the secondary escorts 

replaced the principal escorts but most often just left the group. 

There is often a flow to the formation and dissolution of these groups. They begin 

with a male-female pair (calf may or may not be present) joined by one or more other 

males, with an ensuing chase and competition; this group moving rapidly about the area 

“picking up” additional males and losing males in the process (Darling 1983, Darling et 

al. 1983, Tyack and Whitehead 1983, Baker and Herman 1984, Glockner-Ferrrari and 

Ferrari 1985, Mobley and Herman 1985, Silber 1986). The activity level in the group 

ranges from great speed, 10+ knots, and exuberant lunges, blocks, charges, tail lashes to a 

slow quiet traveling of the group in an apparently stable formation (Darling 1983, Tyack 

and Whitehead 1983, Silber 1986, Clapham et al. 1992). A tentative conclusion is that 

there is a stable formation or arrangement of whales in these groups; it is only when an 

animal changes position, apparently coming closer to the female, that the activity 

increases (Darling 1983, Silber 1986). After a period of time ranging from minutes to 

many hours, the group breaks up, leaving a pair or pair with calf which may or may not 

include the same escort male. A study in the West Indies reported displacements of 
25 

principal escorts by other whales on average every 7.5 hours, and in seven of 10 instances 

the displaced escort left the group (Tyack and Whitehead 1983). Glockner-Ferrari and 

Ferrari (1985) reported that the occurrence of active groups leads to pair formation and, 

they speculated, eventually to mating. 

Several investigators have suggested that levels of surface and agonistic activity 

are proportional to group size; the larger the group the more activity (Herman 1978, 

Tyack 1982, Tyack and Whitehead 1983). In contrast, Silber (1986) noted that surface 

activity rate and activity rate per individual was negatively correlated with group size, 

suggesting that a single whale was responsible for most of the displays as it threatened or 

clashed with other males, in an apparent attempt to preclude them from approaching the 

female. The majority of such activity was attributed to the principal escort. 

 Social sounds. A feature of larger, active, competitive groups are a wide range of 

loud, energetic, underwater vocalizations referred to as “social sounds” (Tyack 1983, 

Glockner-Ferrari and Ferrari 1985, Silber 1986, Mobley et al. 1988). Male humpbacks 

frequently interrupt such activities such as singing, and rapidly travel distances up to 9 

km to join competitive groups (e.g., Tyack and Whitehead 1983, Silber 1986). Playback 

experiments indicate that the social sounds produced in these groups are the signal that 

elicits this behavior (Tyack 1983, Mobley et al. 1988). 

Silber (1986) found that social sounds occurred almost exclusively in groups 

containing three or more whales and were rarely heard near single whales, pairs, or 

cow/calf groups. Group size changed frequently and a dramatic increase in vocalization 

rate resulted when a new whale entered a group. The vocalization rate was positively 

correlated with group size, suggesting that each group member contributed to overall 

sound production. Overlapping sounds, from two or more whales vocalizing 

simultaneously, were heard often leading to speculation that competing males emitted 

acoustic threats concurrently (Silber 1986). 

 Silber (1986) noted that some large groups exhibited very few vocalizations and 

little surface activity, and proposed that perhaps a temporary social dominance among 

males had been established and number of threats were reduced. The introduction of new 

whales may have upset a balance of social roles which resulted in an increase in the 

number of vocalizations. Silber (1986) further speculated that social sounds act to 

demonstrate aggression or agitation as adult males compete for temporary social 

dominance within the group, and proximity to the female. 

All male group agonistic behavior. Agonistic behavior may also occur between 

groups of two or more males without a female present (Tyack 1981, Darling 1983, Baker 

and Herman 1984, Clapham et al. 1992, Darling and Berube 2001). This aspect of male 

interaction is far less clear than when in direct competition for a female. To date, 

observations involving just two males are generally in context of a singer and a male 
26 

which joins it (Darling and Berube, 2001). As discussed above, there is a range of 

behavior that occurs with this interaction, but the majority (22 of 26 interactions in 

Darling and Berube 2001) were non-antagonistic. In the other four cases, these authors 

reported higher energy behavior that included tail lobs, tail throws, breaching and 

flippering by either singer or joiner that could be agonistic in nature but did not develop 

into fights. Tyack (1981) recounts an apparently clear agonistic interaction between a 

singer and a joiner. Clapham et al. (1992) notes the all male groups they described in the 

West Indies could be due to residual aggression following the departure of a female, but 

adds this seems unlikely as most of the groups remained active for extended periods. 

These observations have led to speculation that dominance determination and 

maintenance may be occurring, a seeming necessity of the hypothesized dominance 

polygyny mating system, and reminiscent of land mammals with similar mating behavior 

(Darling 1983, Clapham et al. 1992, Darling and Berube 2001). However, the ongoing 

male relationships theoretically necessary for this type of behavior have not been 

elucidated (Frankel et al. 1995); our understanding of this behavior is very limited, and 

caution in interpretation is appropriate at this stage. 

Cooperative male behavior 

The most striking male-male patterns on the breeding grounds are of threats and 

competition (e.g., Tyack and Whitehead 1983, Baker and Herman 1984) combined with 

reports of male avoidance and spacing (Tyack 1981, 1983; Frankel et al.1995). In 

contrast, several observations suggest the potential for coordinated or cooperative 

behavior among some males, with possible formation of male coalitions to secure access 

to a female. Clapham et al. (1992) introduced this idea after observations of mutually 

non-antagonistic pairings between males in competitive groups involving a female in the 

West Indies, and Brown and Corkeron (1995) supported the notion with the observation 

in Australia of a male pair that moved between competitive groups engaged in agonistic 

displays with other animals, but not each other. Darling and Berube (2001) report an 

observation of males banding together around a singer before joining a competitive 

group, and speculated the song may facilitate this association. Much earlier, although not 

emphasized in their paper, Tyack and Whitehead (1983) noted examples of male pairs 

working as a non-agonistic unit in competitive groups in the West Indies. The working 

idea is that if less dominant animals join competitive groups together rather than alone, 

the odds of one of them outmaneuvering dominant males, and subsequently mating, may 

increase (Clapham et al. 1992, Brown and Corkeron 1995). To date the observations are 

limited and details of this behavior are not known. 

 Pack et al. (1998) describe the death of an adult male in a competitive group, 

including the prolonged post death association and contact by another adult male with the 

dead animal. One of the possible explanations offered was that this was a form of helping 

or epimeletic, altruistic-type behavior. This concept may fit with some form of extended 

association between individual males. Other hints of extended associations of adult 

whales (sexes unknown but likely males as no such associations of females have been 
27 

reported) within Hawaiian waters are given by Cerchio et al. (1998). These observations 

raise the possibility of a complexity in male interactions and behavior beyond initial 

descriptions, and if proven, may require re-interpretation of some observations. 

Female Behavior Patterns 

Female behavior patterns in Hawaii fall into two separate, and quite mutually 

exclusive, realms: 1) mating, and 2) birth and newborn care. For the majority of females 

on a two or three year birth cycle it is one or the other activity in any one year. Females 

that come to Hawaii are either late-lactating (with yearling), resting (neither pregnant or 

lactating), or late pregnant (Dawbin 1966, Gabriele 1992). For the first two categories of 

females the primary objective is presumably to mate, then return to feeding grounds. For 

the last category the objective is birth, protection of newborn, and preparation of the calf 

for return to the feeding grounds. As discussed above there is generally a substantial 

timing difference between the females: those there to mate are among the first to arrive 

and first to leave; those pregnant and birthing are the last to arrive and the last to leave. 

This translates into significant differences in time spent on feeding grounds: pregnant 

cows, 6.5 months; lactating cows, 4.5 months (Gabriele 1992). Female behavior varies 

dramatically with their objectives. On one hand selection of a mate may involve 

maximizing contact with males; whereas birth and newborn care involve minimizing 

contact with males (Gabriele 1992, Smultea 1994). As discussed earlier, an unknown 

portion of individual females undergo post-partum ovulation with mating activity 

occurring shortly after birth. For females that both give birth and mate a mid-season 

change in behavior must occur, but it is currently unclear if this is initiated by the female 

as a reproductive strategy, or simply the result of harassment by males. 

Female mating strategies 

Knowledge of humpback whale female mating strategies and behavior is very 

limited; in fact it may be the least known aspect of humpback whale behavior. 

Theoretically, just as males behave to maximize number of matings, females employ 

strategies to maximize their reproductive success (Emlen and Oring 1977). Gabriele 

(1992) suggests two potential female strategies: 1) accomplish mating while spending the 

least amount of time fasting on the breeding grounds for overall energetic considerations, 

and 2) when on breeding grounds maximize the number of males and minimize the 

number of females encountered. She notes that although overt physical competition for 

matings is apparently absent between female humpbacks, the mere presence of other 

estrus females during their own limited estrus constitutes competition for male attention. 

Female associations on the breeding grounds are extremely rare (Baker 1985) and 

cows with calves at least generally appear to show active avoidance of each other 

(Herman and Antinoja 1977, Tyack 1981, Darling 1983, Glockner 1983, Tyack and 

Whitehead 1983, Baker and Herman 1984, Baker 1985, R. Cartwright pers.comm. 2001). 
28 

Tyack and Whitehead (1983) note that only twice was more than one cow with calf 

observed in any group at one time: once on Silver Bank two calves were seen together 

during the apparent accidental merging of two groups, which happened to be in same 

place at same time, but soon diverged; and once in Hawaii two calves were seen in a 

group of seven whales that was stable over an hour (no further details given). Darling 

(1983) reported one observation in Hawaii of two competitive groups each including a 

cow with calf that ran into each but soon separated. Between 1999-2001 off Maui, R. 

Cartwright (pers. comm. 2001) observed three incidences of short-duration multiple 

cow/calf groups, the longest interaction lasting 23 minutes. Glockner-Ferrari and Ferrari 

(1985) report one competitive group with two females, but felt one was a sub-adult. 

Clapham et al. (1992) in studies of the West Indies note only one case where a second 

female briefly joined and left a group that already contained a female. In Mobley et al.’s 

(1988) playback experiments, although the broadcast of feeding sounds (thought to be 

made by females) attracted the most whales, no female with calf ever approached them. 

 Female adult humpbacks in Hawaii are found alone with a calf (non-mating 

situation), in pairs with an adult male, and in larger competitive/active groups with 

multiple males. Females both without and with calf are found in these latter groups, 

although calf presence increases later in the season (Darling 1983, Gabriele 1992). 

Female mating behavior patterns include: 1) acceptance of a single male escort; 2) 

leading (or being chased by) groups of multiple competitive males; and 3) presumably 

mating. A proposed female behavior pattern, entirely speculative but commonly implied 

in the literature, is choice of males by their song. Lone adult females have been 

documented, but are a rare occurrence on the breeding grounds (Darling 1983, Gabriele 

1992). 

As mating has not been observed, it is a presumption that females identified in 

pairs and multiple male groups are involved in mating behavior. The following 

interactions have been observed within pairs or larger groups of adults suggesting mating 

or attempts at it: 1) females were followed or chased by males; 2) excited rolling and 

flippering in close proximity or contact with other whales; 3) female tail arching, or 

contorting of the tail stock into a “S” shape occurred suggesting presentation of the 

genital area; 4) “nosing” of female genital area by males, possibly checking reproductive 

condition; and 5) females rolling away from males, or extending the tail out of the water, 

apparently to put the genital area above the surface, suggesting avoidance actions 

(Darling 1983). 

 There are a number of examples of females observed with single or multiple male 

groups during one winter, re-identified with calf the following winter. Table 4 provides 

several of these examples from the literature. These observations, combined with the 

understood gestation period of 11-12 months (e.g., Chittleborough 1965), suggest the 

possibility that mating occurred in the pair or multiple male group. 
29 

Table 4. Behavior of females the year previous to giving birth 

Darling (1983) Eight examples of females identified as one of a pair of adults or in large 

groups of adults in the years they were not identified with a calf. In two 

cases the animal accompanying a female in a pair was a known male. 

Also, two cows which gave birth in consecutive years were accompanied 

by either a single escort or multiple males in the year before the 

consecutive birth. 

Glockner-Ferrari and Ferrari 

(1985) 

A whale that had a calf four years in succession was accompanied by an 

escort on each of the seven sightings during the four years it was 

observed. 

Gabriele (1992) In 13 of 16 cases where females identified with a calf had also been seen 

the previous season their behavioral characteristics were: typical pod size 

= 2; the other individual was very likely a male; and typical pod behavior 

was breathing and diving only. 

Specific Examples (from Darling 1983) 

A. Examples of behavior 

patterns of a pair which 

included a female which gave 

birth the following year 

E.g. 1. Cow #13 was identified on 3 March 1980 in a pair, and in the 

following season with a calf. The other member of the pair on this date 

was not sexed, but was seen in a group of five to seven adults earlier in 

the day suggesting it was far more likely a male than a female. This pair 

was milling with significant surface activity including flippering, 

breaching, rolling belly up, and one animal swimming upside down close 

to the surface just prior to blowing. The behavior patterns were not 

correlated with a specific animal. 

E.g. 2. Cow #17 was identified twice in a pair, 30 January and 18 

February 1980, the year before it was seen with a calf. The partner on 

each occasion was different. On 30 January it was a known male. The 

only behavior noted was that the male lifted its head above the water 

when it was swimming beside the female. The male had a raw, bloody 

area on its peduncle, probably the result of an aggressive interaction 

between it an other males over access to the female. 

B. Examples of behavior in a 

larger group which included a 

female that gave birth the 

following year 

E.g. 1. Cow #15 was identified in a group of 4+ adults the year before it 

was identified with a calf. The behavior of this group included flippering 

and rolling, along with a variety of apparently aggressive interactions 

including head lifts, chin slaps, jaw claps, tail lashes and bubble streams. 

Specific behavior patterns were not correlated with individuals. 

E.g. 2. Cow #18 was identified in large groups on 1 and 6 February 1980, 

the year before it was found with a calf. On 1 February it was first seen 

with a group of 4+ adults and later in a group of 8+ adults (probably the 

same core group with additional animals). The behavior patterns noted 

were flippering, head lifts, jaw claps, tail lobs and underwater blows. This 

example also indicates that a female may be close enough to estrus over a 

period of six days to attract males. 

 
30 

Pair - Female with male 

Pairs of adult humpbacks are a common social group in Hawaii and other winter 

assembly areas. Studies have shown these may be either a female and male (as is 

functionally the case in cow/calf and escort groups) or two males (Darling 1983, Clapham 

et al.1992, Darling and Berube 2001). Female-male pairs are relatively (in comparison to 

larger groups or male pairs) stable, often maintaining a calm, exclusive union for hours to 

a day or longer (Darling 1983, Baker and Herman 1984, Glockner-Ferrari and Ferrari 

1985, Mobley and Herman 1985, Gabriele 1992). Instances of conclusive sexing of both 

individuals when a calf is not involved, combined with extended behavioral observations, 

are limited, however general patterns that are likely female-male follow. 

Female-male pairs have been observed traveling, however, the most common 

behavior pattern has been of the pair stationary as shown in Figure 8, making nearsynchronized long dives of 20-30 minutes or more (Darling 1983, Gabriele 1992). These 

long dives separated only by three to four blows at the surface have caused this behavior 

to be referred to by some researchers as “breathholding” and the whales as 

“breathholders” (e.g., Darling 1983). Underwater observations indicated that these pairs 

dive to approximately 50-100 ft, and stop, remaining virtually motionless. Often one 

whale was in a more horizontal position, and the other a more vertical, head down, 

position. Beyond this, there was notably little overt or obvious interaction or activity 

between the whales (Gabriele 1992, Darling unpublished notes). In a few observations 

one of the whales was singing (Darling, unpublished notes). Gabriele (1992) noted that 

breaching, flipper slapping, head lunging, underwater blows and fluke slaps occurred in 

these groups, but infrequently. The behavior is markedly similar, and likely identical, to 

an escort with cow and calf – minus the calf. These pairs tend to persist until another 

adult (male) joins, potentially leading to formation of a larger competitive group, and may 

result after a larger group has broken up (Glockner-Ferrari and Ferrari 1985). The 

development or instigation of these pairs is not understood, but apparently they are 

mutually acceptable as there is no obvious escape behavior. The most likely explanation 

is of a female approaching estrus and accepting the male attention, or alternatively, 

having mated, allowing a guard against unwanted attention (Mobley and Herman 1985). 
31 

Figure 8. Female-male pair. Often the pair of adults lie motionless approximately 5-15 m below the surface 

for periods of 15-30 minutes or longer. They usually surface together for three to four blows, then 

immediately return to this sub-surface position. This is presumed to be primarily a female-male pair 

behavior, but sex determination data is limited. These are commonly referred to as “ breathholders.” 

 Females in competitive groups 

During the breeding season an adult female (with or without calf) is, with few 

exceptions, the center or focus of competitive groups of two to 20 or more males, with all 

the attendant competitive and aggressive activity described above (Darling 1983, Darling 

et al. 1983, Tyack and Whitehead 1983, Baker and Herman 1984, Glockner-Ferrari and 

Ferrari 1985, Clapham et al. 1992). 

It is likely that the competitive groups are ultimately a test of male fitness, with 

the most “fit” gaining access to the female. Following this presumption is the speculation 

that the female, by moving rapidly in front of the group and leading it over substantial 

distances: 1) avoids unwanted matings, and/or 2) attracts as many males as possible 

thereby increasing the level of competition in the group and ultimately gaining a more fit 

mate (Tyack and Whitehead 1983). 

As noted above, there is consistent evidence that singers may stop singing and 

join competitive groups as they move within range, and that social sounds made in these 

groups are the signal that attracts the incoming males (Tyack 1981, Darling 1983, Tyack 

and Whitehead 1983, Baker and Herman 1984, Glockner-Ferrari and Ferrari 1985, 
32 

Mobley and Herman 1985, Silber 1986, Mobley et al. 1988, Darling and Berube 2001). If 

females were trying to attract males it would seem to make sense for them to be making 

the social sounds. However, currently there is no evidence that females make sounds in 

these groups, and observations suggest it is primarily, if not solely males, doing so (Silber 

1986). This raises several questions, including whether or not the purpose of females 

leading these groups is really to attract additional males as speculated. 

Female humpback whales have appeared to influence selection of mates in several 

other ways, such as avoiding unwanted mating by moving genital region from the water 

(Darling 1983), or behaving aggressively towards a sub-adult male (Clapham et al. 1992). 

Glockner-Ferrari and Ferrari (1985) report seven occasions where the female led males to 

shoreline or to vessels, resulting in change of escort or retreat of males; Mattila et al. 

(1988) suggests females lead groups into areas with many coral heads in the Silver Banks 

with the same objective. Baker and Herman (1984) report that fluke slaps, inverted fluke 

slaps, flipper slaps, and breaches were most commonly associated with the behavior of 

the lead animal in competitive groups and suggest these are a response of the female to 

the aggression and advances of the competitors. 

Females choosing males via song? 

There has been substantial speculation that females exercise choice of mates 

though listening to their song (e.g., Winn and Winn 1978, Tyack 1981, Herman and 

Mobley 1985, Chu 1986, Chu and Harcourt 1988, Helweg et al. 1992, Frankel et al. 

1995), and such female choice may be the driving force behind song change (Tyack 

1981). However, there is no evidence for this, and only very limited data suggests females 

may actively join singers. 

Two studies have reported, collectively, three instances of known females joining 

singers (Tyack 1981, Medrano et al. 1994). Tyack (1981) gives one example of a female 

with calf that joined a singer, and Medrano et al. (1994) report two observations of 

females joining singers. One of these involved a cow and calf that joined a singer, and the 

other a pair of adults that approached a singer, one of which, later genetically determined 

to be a female, joined it. In addition, there have been several cases where females 

approached the experimental playback of songs, although as noted by Mobley et al. 

(1988), these were the exception. These observations have subsequently been discussed 

widely (e.g., Baker and Herman 1984, Mobley et al. 1988, Frankel et al. 1995, Clapham 

1996, Au et al. 2000) in the context of the song as advertisement to females. As 

mentioned above, some researchers have speculated that males have two alternative 

strategies for gaining access to females: 1) singing and 2) joining a larger competitive 

group (e.g., Tyack and Whitehead 1983, Frankel et al. 1995, Helweg et al. 1992, Au et al. 

2000). From a female perspective this suggests they may select males through song or by 

encouraging aggressive contests. 
33 

Selection of males by females via the song may be the best known unproven 

hypothesis regarding the breeding behavior of humpbacks. Considering the evidence 

building that the song is primarily a signal between males (Darling and Berube 2001), the 

failure of song playback experiments to regularly attract females (Mobley et al.1988), and 

very few actual observations of females joining singers, some clear behavioral evidence 

that female choice of singers actually occurs is needed to retain a “female attraction” 

hypothesis. This is a significant issue in terms of characterization of humpback behavior 

in Hawaii – both male and female. 

In acknowledgment of the lack of evidence that song attracts females, several 

researchers have proposed that the response of females need not be an approach to the 

singer, but instead an “invitation” for the male to approach her (Helweg et al. 1992). 

Mobely et al. (1988) suggest a female may indicate her preference for a particular singer 

and hence a particular song by whether she allows the pursuing singer to join her, or 

perhaps a return vocalization (that has not been heard or listened for). They suggest then 

that although the song may not serve to bring females directly to singer, it may still serve 

as a basis for female selection. Another suggestion is that the song may simply allow 

females to locate and evaluate singers, and females may lead a competitive group toward 

the loudest deepest song she hears, inviting the singer to compete (C. Gabriele pers. 

comm. 2001). 

Birth and Young 

The context for behavior patterns of late pregnant or recent postpartum females is 

maintenance of circumstances that are optimal for rest, nursing and protection of young, 

including avoidance of sexually active males. Females with young, as shown in Figure 9, 

may separate themselves from mating activity spatially, utilizing inshore shallow areas 

(e.g., Smultea 1994, Mobley et al. 1995), and perhaps temporally, seeking this refuge 

when courting or aggression increases, daily or seasonally (Smultea 1994). Also, there is 

speculation that some births occur prior to the peak of the mating season, and postpartum 

ovulation occurs some weeks after birth, further providing some degree of space between 

birth and mating activities (Glockner and Venus 1983, Mobley and Herman 1985, 

Glockner-Ferrari and Ferrari 1990). 
34 

Figure 9. Cow with young calf. Cows with newborn young are commonly sighted through the winter often 

in shallower or more inshore waters than the adult population. 

 In a study of habitat use on the Kona coast of Hawaii, Smultea (1994) concluded 

that humpback groups containing a calf occurred in significantly more shallow water and 

nearer to shore than did groups without a calf during afternoon hours and, late in the 

season, throughout the day, apparently coinciding with increased male activity. She 

concluded that adults without a calf may use deep water to facilitate breeding behavior 

while maternal females may use shallower water to avoid harassment and injury to calves 

from sexually active males, turbulent offshore conditions or predators. This is consistent 

with other observations of humpbacks (e.g., Whitehead and Moore 1982, GlocknerFerrari and Ferrari 1985), as well as gray and right whales (Jones and Swartz 1984, Payne 

1986). It is thought that conspecific encounters could result in premature social 

interactions with the calf, increased energy expenditure, interruption of nursing bouts, 

mistaken imprinting or nursing attempts, potential separation of calves from cows and 

even injury to calves (Jones and Swartz 1984, Thomas and Taber 1984, Smultea 1994). 

 Little is known of the impact of predation on the behavior of humpback whales in 

Hawaii. Potential predators in the area include false killer whales (Pseudorca crassidens) 

pygmy killer whales (Feresa attenuata), killer whales (Orcinus orca) and sharks, 

particularly tiger sharks (Galeocerdo cuvier). Killer whales are rarely seen in Hawaiian 

waters, however they are certainly a predator in cooler seas (Chittleborough 1953, Steiger 

and Calambokidis 1995). Predation by false and pygmy killer whales could well be a 

factor in behavior, especially considering an anecdote by a fisherman of false killer 

whales attacking a calf off the island of Hawaii (Darling 1990 p.52). Whether this is a 

rare or common occurrence is unknown. Tiger sharks are clearly a significant predator in 

the Hawaiian breeding area, with observations of them following apparently sick calves 

(F. Nicklin pers. comm., 2000), and attacking living but entangled adults (M. Jones pers. 

comm. 2001). However, whether they actively pursue healthy calves is not known. There 
35 

are suggestions that shallow water may confound echolocation abilities of odontocetes, 

and otherwise minimize the vulnerability of calves from below (Wursig and Wursig 

1980; Thomas and Taber 1984). 

Birth 

A most striking non-observation in Hawaii is a birth. During tens of thousands of 

observation hours through the whale watching industry, as well as multiple researchers 

present over 25 years, a birth has not been documented. This may reflect just how critical 

separation of birth from activity in the region is. This separation may be accomplished 

seasonally (before Hawaii), spatially (simply away from all activity), or perhaps by 

occurring nocturnally. 

At the same time there is little question that birth occurs during the winter season. 

Extensive examination of dead whales indicate peak ovulation (with gestation of 11-12 

months), term fetuses and birth coincide with winter months (e.g., Chittleborough 1958, 

Nishiwaki 1959). Direct evidence from Hawaii includes observations of: 1) tiny calves 

with folded dorsal fins and crease marks clearly within days if not hours of birth (e.g., 

Darling 1983, Glockner-Ferrari and Ferrari 1985, Cartwright 1999); 2) on 11 January 

1994 a humpback placenta was found within 15 minutes of a young calf appearing with a 

female (Silvers and Salden 1997); and 3) one sighting of a female without calf on 31 

January 1981 and with a calf on 16 February 1981, 17 days later, apparently indicated a 

birth occurred (Darling 1983). 

Newborn behavior 

The earliest published record of a cow with young calf in Hawaii is 24 December 

(Craig and Herman 1997), however whale-watch sightings of newborn calves are reported 

prior to that date (M. Jones pers. comm. 2001). Past studies suggested cows with 

newborn were relatively rare through January (e.g., two pairs in five seasons, Darling 

1983) until early February (Baker and Herman 1984, Glockner-Ferrari and Ferrari 1985), 

but there is little current information on cow/calf abundance in the early winter season. 

After 1 February the numbers of cows with calves increase markedly. They are commonly 

sighted, and are the last groups present in late May and June (Glockner-Ferrari and Ferrari 

1985, Gabriele 1992). Although density of cow/calf pairs can be high in mid-season, they 

generally maintain an active separation from each other. 

Cows with newborns apparently travel and circulate though the island chain as do 

other social groups. Day to day resights of specific cows with calves in one location are 

not common (Darling 1983, Glockner-Ferrari and Ferrari 1985, Craig and Herman 1997). 

Mate et al. (1997) satellite-tagged a cow with calf that soon after began the northward 

migration traveling 150 km per day. In subsequent tagging of cows earlier in the season 

he found extensive movement between at least the Maui and Penguin Banks regions (B. 
36 

Mate pers. comm. 2001). The purpose, or cause, of this steady movement is not known; 

perhaps it is part of the swimming regimen preparing the calf for migration, or possibly 

the result of the cow being pursued or harassed by males. Cartwright (1999) found that 

travel was by far the most common activity of cows with calves occurring 55% of 

observation time, and increasing with single or multiple escorts. Rest was the next most 

common activity, occurring in 12% of observation time. 

A commonly observed cow/calf behavior pattern is resting. As described by 

Glockner-Ferrari and Ferrari (1985), the cow lies in a horizontal position at a depth 

ranging from approximately 10-20 m below the surface. The calf usually positions itself 

above the mother’s head or directly below the chin as in Figure 10. The calf rises slowly 

to the surface by itself every two to six minutes to blow three or four times while 

swimming in circular pattern (Glockner and Venus 1983). The calf then descends to its 

mother (which may surface every 10-20 minutes). Often the calf will twirl its body and 

swim upside down. Physical contact frequently occurs between the mother and calf. 

Figure 10. Cow with young calf resting. A typical resting position is with the calf under the cow’s head, 

often in contact with its mother. 

The calves nurse throughout their first winter, the process of weaning beginning 

between six and 10 months of age (Clapham 1996), and culminating in separation after 

the first feeding season. Glockner-Ferrari and Ferrari (1985) describe suckling occurring 

while the cow was lying stationary in a horizontal position at a depth of 30-50 ft. The calf 

positioned itself below the cow at approximately 30 degree angle to the midline of her 

body, the tip of its mouth touching her mammary slit. In one case they observed the calf’s 

jaws opening and closing. After the calf stopped suckling the cow and calf slowly moved 

on. On another occasion they observed suckling while the animals were traveling 

(Glockner-Ferrari and Ferrari 1985). 
37 

Play by the calf, perhaps in the form of mimicry, seems an important element of 

newborn behavior in Hawaii. Glockner-Ferrari and Ferrari (1985) note that on many 

occasions they observed the calves imitate the behavior of their mothers by repeating the 

behavior immediately after the mother has performed it, including breaching, tail 

throwing, tail slapping, and flippering. In 1983 these authors observed calves imitate the 

behavior of the escort, performing head lunging, throat expansion, chin slapping and 

bubble streaming. Cartwright (1999) describes calf surface behaviors, including 

flippering, spyhops (head rise), twirling (roll), tail slaps (lob), tail swishes (lash), 

peduncle (tail) throws, head lunges, full breaches and half breaches (belly flop), all 

activities seen in adults (terms in parentheses are those given in Appendix 2). 

Although generally not vocal, at least compared to singers or competitive groups, 

calves do occasionally produce sounds, with at least a single grunt type vocalization 

(Glockner-Ferrari and Ferrari 1985, F. Nicklin pers. comm. 2000). Glockner-Ferrari and 

Ferrari (1985) note one occasion when they heard loud continuous vocalizations but were 

unable to determine if sounds were being emitted by the calf, mother or both. 

Acceptance of escort by cow with calf 

As described previously the cow/calf and escort trio, as illustrated in Figure 11, is 

a commonly observed social group in Hawaiian waters and has a relatively high level of 

stability versus other groups (Glockner-Ferrari and Ferrari 1985, Mobley and Herman 

1985). The behavior of mothers and calves is often influenced by the presence and 

behavior of the escort, and the presence of pursuing males (Glockner-Ferrari and Ferrari 

1985, Cartwright 1999). 

Figure 11. Cow/calf and escort. The stability of these groups suggests the cow accepts the male escort, 

possible gaining some protection from harassment by other males. 
38 

Cartwright (1999) studied the impact of single and multiple escorts on cow/calf 

behavior. She determined that as escorts join the mother/calf pair the energy demands of 

the behavioral regime increase, although much more so in the case of multiple escorts 

versus single escorts. Cartwright (1999) noted that the stability of the mother/calf and 

escort group indicates that this association is a choice made by both the mother and 

escort, and suggested that, as there is some energetic cost to this association for the 

mother due to changes in the time budget, there must be some benefit (as per Krebs and 

Davies 1996). The mother may associate with single escort as a trade off; the single escort 

raises the energy expenditure of the group to some degree, however multiple escorts have 

the potential for a far greater negative impact. By associating with a single escort the 

mother may avoid or minimize the impact of harassment by groups of other males 

(Cartwright 1999). 

Juvenile behavior 

A segment of the Hawaii whale population is juvenile, including recently weaned 

yearlings and whales up to four to five years old and sexual maturity. There are few 

studies and limited information on behavior of these younger whales, in part because they 

can be difficult to detect or identify reliably. 

 Some yearlings make their first winter migration to Hawaii with their mothers, 

then separate, and older juveniles are also present to some degree, at least earlier in the 

season (Dawbin 1966, Glockner-Ferrari 1985, Gabriele 1992). Glockner-Ferrari and 

Ferrari (1985) documented three whales as both calves and yearlings. One calf was reseen 

as a yearling still with its mother and reseen as a two year old with two other whales 

neither its mother, indicating some juveniles return to Hawaii. However, as Craig and 

Herman (1997) note, there is evidence that not all juveniles make the entire migration. 

Sub-adults, generally defined by visual size estimations, are often noted on the 

periphery of other social groups including cow/calf pairs, adult pairs and larger groups of 

adults – following the action but not intimately involved (e.g., Glockner-Ferrari and 

Ferrari (1985), Darling and Berube 2001). Glockner-Ferrari and Ferrari (1985) report subadults: 1) in active groups; 2) with adult males; 3) accompanying each other (in pair); and 

4) alone (one of the lone sub-adults a female). These authors note two occasions where 

yearling-sized whales were with an adult male and engaged in apparent sexual activity; in 

one interaction observed for three hours they were, “rubbing against each other twirling 

and swimming upside down and rolling together caressing each other with their flippers.” 

At one point the penis of the sub-adult was extended and rubbed against the genital slit of 

the adult. Glockner-Ferrari and Ferrari (1985) also report an instance where a sub-adult 

with a male was the apparent object of a fight between adult males. Darling (1983) 

reports a much smaller animal, presumed to be yearling or older juvenile, staying around 

an adult singer. 
39 

Other reported behavior attributed to sub-adults in Hawaii includes an apparent 

feeding lunge through mackerel (Salden 1989), and there is some speculation that many 

of the whales that approach boats and divers, and swim for extended periods in close 

proximity to them, are sub-adults (JDD). 

DISCUSSION 

More is known more about humpback whale social organization and behavior 

than any of the other great whales, due in large part to concentrations of humpback 

whales in nearshore and relatively calm locations worldwide; this offering accessibility to 

researchers. It is important, however, to remain aware that overall our knowledge is still 

very young, with many of the topics discussed the result of just one or two papers; many 

the result of the authors’ first impressions and insights; many at the hypothetical stage and 

with a high proportion of speculation. This is a progress report only – a collection of often 

incomplete observations, with some ideas of what they might mean. 

Any attempt to outline what we do not know about humpback behavior would 

make for a longer report than this one. Not only has research to date raised as many 

questions as answers, there are entire realms barely addressed, with examples including 

predation, behavior at night, or age-related changes in behavior. And, there is the reality 

that neither birth or copulation has been documented. When this finally occurs it may 

cause us to revisit many of the tentative conclusions to date. There are several major 

streams of investigation into humpback behavior in Hawaii, some with beginnings in the 

early studies in the 1970s, that, as they are pursued, will contribute enormously to our 

understanding of the animals. 

The fundamental question, What qualities attract humpbacks to Hawaii?, has not 

been adequately addressed. It is apparent that the warm water and shallow banks are a 

consistent feature across humpback breeding areas, however there are strong suggestions 

that mating and birth (or at least behavior associated with mating and young calves) occur 

enroute, in colder, deeper water. We do not know if the whales are seeking out this 

physical habitat, if the assembly is primarily social, the specific location not important, or 

if this entire migratory cycle is simply the optimal physiological/energetic pattern 

considering food seasonality. There is a notion that females seek out Hawaii assembly 

conditions for calving, and this governs the behavior or males that follow for mating 

purposes. This may indeed be the case, however it is apparent that most females do not 

give birth the same year they mate, so the question remains as to why they (and the males) 

make the journey. On the other hand if, as proposed, a female strategy is to maximize 

contact with males over as little time as possible, perhaps the males set up in Hawaii 

knowing the females will come. Understanding the critical attributes of the habitat and 

behavioral dynamics of the assembly is crucial in defining meaningful conservation 

strategies. 
40 

One continuing stream of questioning is whether humpback whale social 

organization patterns and behavior vary with different geographic locations and the 

associated habitat within the main Hawaiian Islands. Initially it was proposed that some 

level of segregation of whales between islands existed. As this is apparently not the case, 

the question then shifted to whether the proportion of specific social groups and related 

behavior patterns vary between islands/locations. Although growing evidence indicates 

individual movements are characterized by rapid, un-directional circulation throughout 

the islands, there remain questions of differential use of locations. Although it is clear 

cows with young calves are more likely to occupy shallow inshore areas than other social 

groups, the purpose and importance of this behavior is entirely speculative. The 

fundamental question is whether there is a direct relationship between habitat type and 

behavior, or if habitat availability correlates with density of whales, which in turn 

determines behavior patterns. 

Humpback whale reproductive strategies and the related behavior of males and 

females remain the focal subject of studies in Hawaii. Male behavior patterns are 

hypothesized, but far from established. The stream of thought has gone the full spectrum, 

from males acting independently perhaps within a dominance order, and either avoiding 

each other or fighting over females, to the possible existence of non-agonistic groups that 

may cooperate in mating. Males are in continual contact through the song, whose function 

is still not clear. There are hints of coherence of groups of males over time, and caregiving behavior between males – even after death. The existence of variable relationships 

between individual males through a dominance order or otherwise, and how these are 

established and maintained, remains to be explored. Differential mating success between 

males, as implied by mating system hypotheses can only be determined genetically and 

such studies are not yet underway in Hawaii. The key to characterization of mating 

behavior is the ongoing testing of predictions of the hypotheses of dominance polygyny, 

lekking, or cooperative behavior and either accepting or rejecting these ideas. 

Female mating strategies, a key to characterizing overall behavior in Hawaii, are 

one of the least understood aspects of humpback behavior. How females choose, or 

otherwise influence the selection of a mate is not known. Proposals that females choose 

males on the basis of the song advertisement have not been proven. There is no indication 

that females are attracted to singers, however it is possible the females may both react to 

and potentially control the song in some, as yet undiscovered, way. The ideas that female 

strategies include selective migratory behavior to breeding grounds, and maximizing 

contact with males in as short as time as possible seem logical but require testing. It 

remains unclear if the postpartum mating that occurs is a female strategy to maximize 

reproductive success, or the result of harassment of males in a one-sided sex ratio. 

Cows and calves have been the focus of studies in Hawaii since the late 1970s, 

with major contributions in describing general behavior and individual reproductive 

histories. However, behavior patterns at birth, and the factors that affect its success and 

the survivorship of newborn have not been defined. It is likely birth and the nurturing of 

newborn are one of the primary reasons humpback whales are in Hawaii, yet we have 
41 

little idea of their habitat or social requirements. As cows with calves occupy the most 

inshore, shallow waters in Hawaii, their interaction with human activities and pollution 

can be significant – yet we do not know enough about natural patterns to adequately 

identify what the impacts may be. 

These are all substantial realms of inquiry, each with many specific topics and 

questions that need to be addressed to conclusively characterize the behavior of 

humpback whales. Hawaii will be one of the key locations in the world where this occurs, 

due to its calm lees, warm waters, density of whales, and accessibility. 

ACKNOWLEDGMENTS 

I gratefully acknowledge the reviews of early drafts and other contributions to this 

report by Chris Gabriele and Meagan Jones. Sal Cerchio provided comments on the 

mating hypotheses. Josie Cleland assisted in many aspects of the production of the report. 

Flip Nicklin graciously provided photographs and video to illustrate the behavior 

patterns. Photographs were taken under NMFS Research Permits 987 and 753. 

LITERATURE CITED 

All included in Appendix 1 
42 

APPENDICES
43 

APPENDIX 1 

HAWAIIAN HUMPBACK BEHAVIOR AND RELATED LITERATURE 

Reports Resulting from Research in Hawaii 

Published Papers: 

Au, W.W.L., J. Mobley, W.C. Burgess, M.O. Lammers, and P.E. Nachtigall. 2000. 

Seasonal and diurnal trends of chorusing humpback whales wintering in waters 

off western Maui. Marine Mammal Science 16(3):30-544. 

Baker, C.S. and L.M. Herman. 1981. Migration and local movement of humpback whales 

in Hawaiian waters. Canadian Journal of Zoology 59. 

Baker, C.S. and L.M. Herman. 1984. Aggressive behavior between humpback whales 

(Megaptera novaeangliae) wintering in Hawaiian waters. Canadian Journal of 

Zoology 62:1922-1937. 

Baker, C.S. and L.M. Herman. 1984. Seasonal contrasts in the social behavior of the 

humpback whale. Cetus 5 (2):14-16. 

Baker, C.S., A. Perry, and L. M. Herman. 1987. Reproductive histories of female 

humpback whales, Megaptera novaeangliae, in the North Pacific. Marine Ecology 

Progress Series 41:103-114. 

 

Baker, C.S., L. Medrano-Gonzalez, J. Calambokidis, A. Perry, F. Pichler, H. Rosenbaum, 

J. M. Straley, J. Urban-Ramirez, M. Yamaguchi, and O. von Ziegesar. 1998. 

Population structure of nuclear and mitochrondrial DNA variation among 

humpback whales in the North Pacific. Molecular Ecology 7:695-708. 

Cerchio, S., C. Gabriele, T.F. Norris, and L.M. Herman. 1998. Movements of humpback 

whales between Kauai and Hawaii: Implication for the population structure and 

abundance estimation in the Hawaiian Islands. Marine Ecology Progress Series 

175:13-22. 

Cerchio, S., J.K. Jacobsen, and T.F. Norris. In Press. Temporal and geographic variation 

in songs of humpback whales (Megaptera novaeangliae): Synchronous change in 

Hawaiian and Mexican breeding assemblages. Animal Behavior. 

Craig, A.S. and L.M. Herman. 1977. Sex differences in site fidelity and migration of 

humpback whales (Megaptera novaeangliae) to the Hawaiian Islands. Canadian 

Journal of Zoology 75:1923-1933. 
44 

Craig, A.S. and L.M. Herman. 2000. Habitat preferences of female humpback whales, 

Megaptera novaeangliae, in the Hawaiian Islands are associated with 

reproductive status. Marine Ecology Progress Series 193:209-216. 

Darling, J.D., K. M. Gibson, and G. Silber.1983. Observations on the abundance and 

behavior of humpback whales (Megaptera novaeangliae) of West Maui, Hawaii 

1977-79. Pages 201-222 in R. Payne, ed. Communication and behavior of whales. 

AAAS Selected Symposia Series, Westview Press. Boulder, CO. 

Darling, J.D. and D.J. McSweeney 1985. Observations on the migrations of North Pacific 

humpback whales (Megaptera novaeangliae). Canadian Journal of Zoology 

63:308-314. 

Darling, J.D. and M. Berube. 2001. Interactions of singing humpback whales with other 

males. Marine Mammal Science 17(3):570-584. 

Frazer, L.N. and E. Mercado. 2000. A sonar model for the humpback whale song. Journal 

of Oceanic Engineering 25(1):160-181. 

Frankel, A.S., C.W. Clark, L. M. Herman, and C. Gabriele. 1995. Spatial distribution, 

habitat utilization, and social interactionsof humpback whales, Megaptera 

novaeangliae, of Hawaii determined using acoustic and visual techniques. 

Canadian Journal of Zoology 73:1134-1146. 

Frankel. A.S., J.R. Mobley, and L.M. Herman. 1995. Estimation of auditory response 

thresholds in humpback whales using biologically meaningful sounds. Pages 55-

69, in R.A. Kastelein, J.A. Thomas and P.E. Nachtigall, eds. Sensory systems of 

aquatic mammals, De Spil Publishers. The Netherlands. 

Frumhoff, P. 1983. Aberrant songs of humpback whales (Megaptera novaeangliae): 

Clues to the structure of humpback songs. Pages 81-87 in R. Payne, ed. 

Communication and behavior of whales. AAAS Selected Symposia Series. 

Westview Press, Boulder, CO. 

Glockner, D.A. 1983. Determining the sex of humpback whales (Megaptera 

novaeangliae) in their natural environment. Pages 447-464 in R. Payne, ed. 

Communication and behavior of whales. AAAS Selected Symposia Series, 

Westview Press, Boulder, CO.

Glockner, D.A. and S. Venus. 1983. Identfication, growth rate, and behavior of 

humpback whale (Megaptera novaeangliae) cows and calves in the waters off 

Maui, Hawaii 1977-79. Pages 223-258 in R. Payne, ed. Communication and 

behavior of whales. AAAS Selected Symposia Series, Westview Press, Boulder, 

CO.
45 

Glockner-Ferrari, D.A. and M.J. Ferrari. 1984. Reproduction in humpback whales, 

Megaptera novaeangliae, in Hawaiian waters. Reports International Whaling 

Commission, Special Issue 6:237-242. 

Glockner-Ferrari and M.J. Ferrari. 1990. Reproduction in the humpback whale 

(Megaptera novaeangliae) in Hawaiian waters, 1975-1988: The life history, 

reproductive rates, and behavior of known individuals identified through surface 

and underwater photography. Reports International Whaling Commission, Special 

Issue 12: 61-167. 

Helwig, D.A., A.S Frankel, F.R. Mobley, and L.M. Herman. 1992. Humpback whale 

song: our current understanding. Pages 459-483 in J. Thomas et al., eds. Marine 

Mammal Sensory Systems. Plenum Press. New York. 

Helwig, D.A. and L.M. Herman. 1993. Observations of an S-shaped posture in humpback 

whales. Aquatic Mammals 18:74-78. 

Helwig, D.A. and L.M. Herman. 1994. Diurnal patterns of behavior and group 

membership of humpback whales (Megaptera novaeangliae) wintering in 

Hawaiian waters. Ethology 98:298-311. 

Herman, L.M. and R.C. Antinoja. 1977. Humpback whales in the Hawaiian breeding 

waters: Population and pod characteristics. Scientific Reports Whales Research 

Institute Tokyo 29:59-85. 

Herman, L.M. and W.N. Tavolga. 1980. The communications systems of cetaceans. In

L.M. Herman, ed. Cetacean behavior, mechanisms and functions. John Wiley and 

Sons. New York. 

Mate, B.R., R. Gisiner, and J. Mobley. 1998. Local and migratory movements of the 

Hawaiian humpback whales tracked by satellite telemetry. Canadian Journal of 

Zoology 76:863-868. 

McSweeney, D.J., K.C. Chu, W.F. Dolphin, and L.N. Guinee. 1989. North Pacific 

humpback whale songs: A comparison of southeast Alaskan feeding ground songs 

and Hawaiian wintering ground songs. Marine Mammal Science 5:16-138. 

Mobley, J.R.and L.M. Herman. 1985. Transience of social affiliations among humpback 

whales (Megaptera novaeangliae) on Hawaiian wintering grounds. Canadian 

Journal of Zoology 63: 762-772. 

Mobely, J.R., L.M. Herman, and A.S. Frankel. 1986. Sound playback experiments with 

humpback whales in the Hawaiian wintering grounds. Quarterly - University of 

Hawaii Sea Grant College Program. 8(3):1-6. 
46 

Mobley, J.R., L.M. Herman, and A.S. Frankel. 1988. Responses of wintering humpback 

whales (Megaptera novaeangliae) to playbacks of winter and summer 

vocalizations and of synthetic sound. Behavioral Ecology and Sociobiology 

23:211-223. 

Mobley Jr., J.R., G.B. Bauer, and L.M. Herman. 1999. Changes over a ten-year interval in 

the distribution and relative abundance of humpback whales (Megaptera 

novaeangliae) wintering in Hawaiian waters. Aquatic Mammals 25:63-72. 

Pack, A.A., D. Salden, M.J Ferrari, D.A.Glockner-Ferrari, L.M. Herman, H.A. Stubbs, 

and J.M. Straley. 1998. Male humpback whale dies in competitive group. Marine 

Mammal Science 14(4):861-873 . 

Payne, R.S. and L.N. Guinee. 1983. Humpback whale songs as an indicator of “stocks.” 

Pages 333-358 in R. Payne, ed. Communication and behavior of whales. AAAS 

Selected Symposia Series Westview Press, Boulder, CO. 

Payne, K., P. Tyack, and R. Payne. 1983. Progressive changes in the songs of humpback 

whales (Megaptera novaeangliae): A detailed analysis of two seasons in Hawaii. 

Pages 9-57 in R. Payne, ed. Communication and behavior in whales. AAAS 

Selected Symposia Series. Westview Press, Boulder, CO. 

Payne, K.P. and R.S. Payne. 1985. Large scale changes over 19 years in songs of 

humpback whales off Bermuda. Zeitschrift fur Tierpsychologie 68:89-114. 

Silber, G.K. 1986. The relationship of social vocalizations to surface behavior and 

aggression in the Hawaiian humpback whale (Megaptera novaeangliae). 

Canadian Journal of Zoology 64:2075-2080. 

Smultea, M.A. 1994. Segregation by humpback whale (Megaptera novaeangliae) cows 

with a calf in coastal habitat near the island of Hawaii. Canadian Journal of 

Zoology 72:805-811. 

Silvers, L.E. and D.R. Salden. 1997. A large placenta encountered in the Hawaiian winter 

grounds of the humpback whale, Megaptera novaeangliae. Marine Mammal 

Science 13(4):711-716. 

Spitz, S.S., L.M. Herman, and A.A. Pack. 2000. Measuring the sizes of humpback whales 

(Megaptera novaeangliae) through underwater videogrammetry. Marine Mammal 

Science 16:664-676. 

 

Thompson, P.O. and W.A. Friedl. 1982. A long term study of low frequency sounds from 

several species of whales off Oahu, Hawaii. Cetology 45:1-19. 
47 

Tyack, P.L. 1983. Differential response of humpback whales, Megaptera novaeagliae, to 

playback of song or social sounds. Behavioral Ecology and Sociobiology 13:49-

55. 

 Tyack. P. and Whitehead, H. 1983. Male competition in large groups of wintering 

humpback whales. Behavior 83:132-154. 

Tyack, P.L. 1981. Interactions between singing Hawaiian humpback whales and 

conspecifics nearby. Behavioral Ecology and Sociobiology 8:105-116. 

Wolman , A.A. and CM. Jurasz 1977. Humpback whales in Hawaii: Vessel census, 1976. 

Mar. Fish. Rev. 39:1-5. 

Graduate Dissertations: 

Baker, C.S. 1985. The population structure and social organization of humpback whales 

(Megaptera novaeangliae) in the central and eastern North Pacific. Ph.D. 

dissertation. University of Hawaii, Honolulu. 

Bauer, G.H. 1986. The behavior of humpback whales in Hawaii and modification of 

behavior induced by human intervention. Ph.D. thesis. University of Hawaii, 

Honolulu. 

Cartwright, R. 1999. Factors affecting the behavior of humpback whale, Megaptera 

novaeangliae, calves whilst in Hawaiian waters. M.Sc. dissertation. Manchester 

Metropolitan University. 58 pp. 

Cerchio, S. 1993. Geographic variation and cultural evolution in songs of humpback 

whales (Megaptera novaeangliae) in the eastern North Pacific. MSc. dissertation. 

Moss Landing Marine Laboratories, San Jose State University. 72pp. 

Clapham, P.J. 1993. The social and reproductive biology of North Atlantic humpback 

whales, Megaptera novaeangilae. Ph.D. thesis, University of Aberdeen, Scotland. 

Coleman, R.J. 1994. Aerial behavior of the Hawaiian humpback whale. MA. thesis. 

University of Hawaii. 

Craig, A.S. 1995. Site fidelity and reproductive histories of humpback whales in the 

Hawaiian Islands and Southeast Alaska. M.A. thesis. University of Hawaii. 

 

Craig, A.S. 2001. Habitat utilization, migratory timing, and male escorting strategies of 

humpback whales in the Hawaii Islands. Ph.D. dissertation. University of Hawaii. 
48 

Darling, J.D. (1983). Migrations, abundance and behavior of Hawaiian humpback whales 

(Megaptera novaeangliae (Boroski)). Ph.D. thesis. University of California Santa 

Cruz. 147 pp. 

Frankel, A.S. 1994. Acoustic and visual tracking reveals distribution, song variability and 

social roles of humpback whales in Hawaiian waters. Ph.D. thesis. University of 

Hawaii, Manoa, Hawaii. 

Gabriele, C. M. 1992. The behavior and residence characteristics of reproductive classes 

of humpback whales (Megaptera novaeangliae) in the Hawaiian Islands. M.A. 

thesis. University of Hawaii. 87 pp. 

Frankel, A.S. 1994. Acoustic and visual tracking reveals distribution, song variability and 

social roles of humpback whales in Hawaiian waters. Ph.D. dissertation. 

University of Hawaii. 

Helwig, D.A. 1989. The daily and seasonal patterns of behavior and abundance of 

humpback whales (Megaptera novaeangliae) in Hawaiian waters. M.A. thesis, 

University of Hawaii. 

Mercado, E. 1995. An acoustic analysis of humpback whale (Megaptera novaeangliae) 

song units. M.A. thesis. University of Hawaii. 

Mercado, E. 1998. Humpback whale bioacoustics: From form to function. Ph.D. 

dissertation. University of Hawaii. 

Silber, G. K. 1986. Non-song phonations and associated surface behavior of the Hawaiian 

humpback whale (Megaptera novaeangliae). M.A. thesis. San Jose State 

University, San Jose, CA. 

Tyack, P. 1982. Humpback whales repond to the sounds of their neighbors. Ph.D. thesis. 

The Rockefeller University, New York. 

Workshop and Unpublished Reports: 

Baird, R.B, A.D. Ligon, and S. Hooker. 2000. Sub-surface and night-time behavior of 

humpback whales off Maui, Hawaii: A Preliminary Report. Report prepared under 

Contract #40ABNC050729 from the Hawaiian Islands Humpback Whale 

National Marine Sanctuary, Kihei, HI, to the Hawaii Wildlife Fund, Paia, HI. 

Glockner-Ferrari, D.A and M.J. Ferrari. 1985. Individual identification, behavior, 

reproduction, and distribution of humpback whales, Megaptera novaeangliae, in 

Hawaii. U.S. Department of Commerce, NTIS PB85-200772. 31pp. 
49 

Mobley Jr., J. R., R.A. Grotefendt, P.H. Forestell, and A.S. Frankel. 1999. Results of 

aerial surveys of marine mammals in the major Hawaiian Islands (1993-1998): 

Final report to the Acoustic Thermometry of Ocean Climate Marine Mammal 

Research Program (ATOC MMRP). 39 pp. Available from Social Sciences, 

University of Hawaii-West Oahu, 96-129 Ala Ike, Pearl City, HI 95782. 

Norris, K.S. and R.R. Reeves (Eds.). (1978). Report on a workshop on problems related 

to humpback whales (Megaptera novaeangliae) in Hawaii. U.S. Department of 

Commerce NTIS PB280 794. 

Payne, C.M., B. Phillips, and E. Nitta. 1997. Report of the workshop to assess research 

and other needs and opportunities related to humpback whale management in the 

Hawaiian Islands, 26-28 April 1995. U.S. Department of Commerce. NOAA 

Technical Memorandum NMFS-OPR-11. 134 pp. 

Salden, D.R. 1988. Humpback whale breaching behavior in Hawaii. HWRF Report No.1. 

Salden, D.R. 1989. Humpback whale pod size and surface behavior in Hawaii. HWRF 

Report No. 2. 

Salden, D.R. 1990. Variability of humpback whale (Megaptera novaeangliae) pod size in 

Hawaii HWRF Report No. 3. 

Sladen, D.R. 1990. Apparent feeding by a sub-adult humpback whale (Megaptera 

novaeangliae) off Maui, Hawaii HWRF Report No. 4. 

Smultea, M.A. 1992. Habitat utilization patterns of humpback whales (Megaptera 

novaeangliae) off the island of Hawaii. U.S. Department of Commerce NTIS 

PB92-182484. 47 pp. 

Conference Abstracts: 

Salden, D.R. 1989. Apparent feeding by a sub-adult humpback whale (Megaptera 

novaeangliae) off Maui, Hawaii. Abstracts 8th Biennial Conference on the 

Biology of Marine Mammals, Pacific Grove CA, Dec. 7-11, 1989 p. 58. 

Steiger, G.H. and J. Calambokidis. 1995. Evidence of predatory attacks on humpback 

whales off California, Oregon and Washington. Abstracts 11th Biennial 

Conference on the Biology of Marine Mammals, Orlando, Florida, December 14-

18, 1995. p. 109. 
50 

Straley, J. M. Overwintering North Pacific humpback whales in Alaskan waters: Who are 

they? Abstracts 13th Biennial Conference on the Biology of Marine Mammals, 

Wailea, Maui, Hawaii, Nov. 28-Dec 3, 1999. p. 180. 

 

Selected Humpback Whale Papers from Other Locations 

Barlow, J. and P.J. Clapham. 1996. A new birth interval approach to estimating 

demographic parameters of humpback whales. Ecology 78(2):535-545. 

Brown, M.R., P.J. Corkeron, P.T. Hale, K.W. Schultz, and M.M. Bryden.1995. Evidence 

for a sex segregated migration in the humpback whale (Megaptera novaeangliae). 

Proceedings Royal Society London Series B Biological Science 259:229-234. 

 Brown, M. and P. Corkeron. 1995. Pod characteristics of migrating humpback whales 

(Megaptera novaeangliae) off the east Australian coast. Behavior 132:163-179. 

Clapham, P.J. and D.K. Mattila. 1990. Humpback whale songs as indications of 

migration routes. Marine Mammal Science 6:155-160. 

Clapham, P.J., P.J. Palsboll, D.K. Mattila, and V. Oswaldo. 1992. Composition of 

humpback whale competitive groups in the West Indies. Behavior 122:182-194. 

Clapham, P.J. 1996. The social and reproductive biology of humpback whales: An 

ecological perspective. Mammal Review 26:27- 49. 

Chittleborough, R.G. 1953. Aerial observations on the humpback whale M. nodosa. 

Australian Journal of Marine and Freshwater Research 9(1):1-18. 

Chittleborough, R.G. 1958. The breeding cycle of the female humpback whale Megaptera 

nodosa (Bonaterre). Australian Journal of Marine and Freshwater Research 9:1-

18. 

Chittleborough, R.G. 1965. Dynamics of two populations of the humpback whale 

Megaptera novaeangliae (Borowski). Australian Journal of Marine and 

Freshwater Research 16:33-128. 

Dawbin, W. H. 1966. The seasonal migratory cycle of humpback whales. Pages 145-170 

in K.S. Norris, ed. Whales, Dolphins and Porpoises. University of California 

Press. Berkeley. 

Mathews, L.H. 1937. The humpback whale, Megaptera nodosa. Discovery Reports 17:7-

92. 
51 

Matilla. D.K., P.J. Clapham, S.K. Katona, and G.S. Stone. 1988. Population composition 

of humpback whales, Megaptera novaeangliae, on Silver Bank, 1984. Canadian 

Journal of Zoology 67:281-285. 

Mattila, D. K., L. N. Guinee, and C.A. Mayo. 1987. Humpback whale songs on a North 

Atlantic feeding ground. Journal of Mammalogy 68: 880-883. 

Medrano, L., M. Salinas, I. Salas, P. Ladron De Guevara, A. Aguayo, J. Jacobsen, and 

C.S. Baker. 1984. Sex identification of humpback whales, (Megaptera 

novaeangliae) on the wintering grounds of the Mexican Pacific Ocean. Canadian 

Journal of Zoology 72:1771-1774. 

Nishiwaki, M. 1959. Humpback whales in Ryukuan waters. Scientific Reports of the 

Whales Research Institute 14:49-86. 

Nishiwaki, M. 1960. Ryukyuan humpback whaling in 1960. Scientific Reports Whales 

Research Institute Tokyo 15:1-16. 

Nishiwaki, M. 1962. Ryukyuan whaling in 1961, Scientifc Reports Whales Research 

Institute. Tokyo 16:19-28. 

Tomilin, A.G. 1967. Mammals of the U.S.S.R. and adjacent countries, Vol. 9. Cetacea 

(translated by O. Ronen from the 1957 Russian edition). Israel Program for 

Scientific Translations, Jerusalem. 270 pp. 

Straley, J.M., C.M. Gabriele, and C. S. Baker. 1994. Annual reproduction by individually 

identified humpback whales (Megaptera novaeangliae) in Alaskan waters. Marine 

Mammal Science 10(1): 87-92. 

Whitehead, H. and M.J. Moore. 1982. Distribution and movements of West Indian 

humpback whales in winter. Canadian Journal of Zoology 60:2203-2211. 

Other Literature Cited 

Brownell, R.L. and K. Ralls. 1986. Potential for sperm competition in baleen whales. 

Reports International Whaling Commission. Special Issue 8:97-112. 

Darling, J.D. 1990. With the whales. Northward Press. Minocqua, Wisconsin. 158 pp. 

Emlen, S.T. and L.W. Oring. 1977. Ecology, sexual selection, and the evolution of 

mating systems. Science 197:215-223. 
52 

Jones, M.L. and S.L. Swartz. 1984. Demography and phenology of gray whales and 

evaluation of whale-watching activties in Laguna San Ignacio, Baja California sur, 

Mexico. Pages 289-307 in M.L. Jones, S. J. Leatherwood and S. L. Swartz, eds. 

The Gray Whale. Academic Press. New York. 

 

Kellogg, R. 1928. What is known of the migrations of some of the whalebone whales. 

Annual Reports Smithonian Institution 1928. pp. 467-494. 

Krebs, J.R. and N.B. Davies. 1996. Introduction to behavioral ecology. Blackwell 

Scientific. Oxford, UK. 

Lockyer, C. 1981. Growth and energy budgets of large baleen whales from the southern 

hemisphere. Pages 379-487 in Mammals in the seas. Vol 3. Food and Agricultural 

Orgnaization of the United Nations, Rome. 

Scammon, C. M. 1874. The marine mammals of the northwestern coast of North 

America, John H. Carmany and Co. San Francisco, CA. 325 pp. 

Slijper, E.J. 1962. Whales. Hutchinson Co. London. 475 pp. 

Taber, S. and P. Thomas. 1984. Mother-infant interaction and behavioral development in 

southern right whales. Behavior 88(1):42-46. 

Wilson, E.O. 1975. Sociobiology, the new synthesis. Harvard University Press. 

Cambridge, MA. 

Wursig, B. and M. Wursig. 1980. Behavior and ecology of the dusky dolphin, 

Lagenorhynchus obscurus, in the south Atlantic. Fisheries Bulletin. 77(4):871-

890. 
53 

APPENDIX 2 

Actions and Postures of Humpbacks in Hawaii 

The following terms are derived from Darling 1983, Glockner-Ferrari and Ferrari 1985, 

and Gabriele 1992 (adapted from Bauer1986 and Helweg 1989). Alternative terms used 

to for same behavior are in parentheses. Glockner-Ferrari and Ferrari (1985) proposed the 

gender of whales that performed some activities; this is noted by an asterisk. Examples 

are given in Figure 12. 

Displays/Actions of General Population (or not known if sex/age specific)

Side fluke (half fluke, lateral 

fluke display) 

Whale is at the water’s surface with one fluke blade extended above the 

surface; indicative of whale swimming on side 

Inverted posture (belly-up) Whale turns ventral side to surface 

Roll The whale rolls ventral side or belly-up, at times slapping flippers on 

surface as it rolls all the way over 

Head rise (spy hop) Whale raises its head vertically out of the water while stationary with 

flippers outstretched, and without open mouth or extended throat pleats 

Tail extension Whale raises its tail slowly into the air, usually high enough that the 

genital area is above the surface, and holds it there for a time 

Tail arch The whale curves its tail stock and fluke into an “S” shape on horizontal 

plane and holds it here while swimming forward 

Flippering (flipper slap) The whale raises a flipper into the air and slaps it down on the surface of 

the water, once or many (20+) times in succession. Males and females* 

Tail lob (lob tail, fluke slap) Whale extends flukes above the water’s surface and slaps them down on 

the surface of the water. This can occur “right way up” with the whale 

slapping the ventral surface of its flukes on the surface, or the reverse, 

with the whale belly-up slapping the dorsal surface of its flukes on the 

surface; occurs once or many (37+) times in succession. Males and 

females* 

Rear body throw (tail throw, 

peduncle slap) 

The whale throws the rear portion of its body from the water such that 

the edge of its flukes strike the water forcefully. Males and females * 

Belly-flop (half breach) The whale leaps partially out of the water and lands on its belly 

Breach The whale leaps from the water, spinning in the air before re-entry, once 

or many (35+) times in succession. At times two associated whales 

breach simultaneously (double breach). Males and females* 
54 

Displays/Actions Mostly Occurring in Competitive Groups/Situations (males)

Tail lash (fluke swish) One whale lashes its tail, often towards another; can occur with flukes on 

a horizontal or vertical plane; within striking distance or not 

Head lunge The whale lunges forward with most of its head coming out of the water. 

Often principal escort or challenger* 

Underwater blow The whale releases a blast of air from its blowhole below the surface of 

the water, usually just prior to surfacing 

Bubble stream (bubble trail) The submerged whale releases a controlled stream of bubbles from its 

blowhole, leaving a long line or wall of bubbles behind it. Males* 

Bubbling Large bubbles emitted from mouth. Escort or dominant male* 

Air gulp (throat inflation) The whale gulps air on the surface, and thereby extends its throat pleats, 

then releases the air underwater; purpose may be to enlarge throat for 

display or collect air to release underwater. Escort or dominant male* 

Head slap (chin slap) Whale lunges/leaps partially out of the water and strikes the ventral side 

of its head forcefully on the surface 

Head lift (S-shaped posture) The whale travels with its back arched and head above the surface 

Jaw clap The whale opens and closes its jaws, clapping them together, at times 

audibly 

Chasing (tail chasing) One whale rapidly chases another; one may throw its tail upward above 

the surface, with the chaser lunging and slapping its head against the 

water immediately behind the first whale. Males* 

Charge One whale charges at another, often bubble-streaming in the process 

Block One whale blocks the path of another with its body 

Strike One whale intentionally strikes another with its flukes, whether 

underwater or on the surface 

Collision Two whales collide, apparently intentionally 

Trumpeting A whale vocalizes on the surface with a prolonged low trumpet-like or 

foghorn-like sound emitted from the blowhole 
55 

Figure 12. Examples of humpback whale actions and postures. 

Breach Flippering Tail Lob 

Tail Arch Tail Extension Belly 

Bubble Stream Head Lift Rear Bo