EXECUTIVE SUMMARY

In 1997, field studies of the endangered Hawaiian monk seal

(Monachus schauinslandi) were conducted at all of its main

reproductive sites in the Northwestern Hawaiian Islands. These

studies provide information necessary to evaluate (1) the status

and trends of monk seal populations, (2) natural history traits

such as survival, reproduction, growth, behavior, and feeding

habits, and (3) the success of various activities designed to

facilitate population growth.

Results of these studies are best described on a site-bysite basis, and the information presented in this document is

organized accordingly. Pooled site-specific data, however,

provide useful indices of the status and trends of the whole

species, including the total number of pups at the main

reproductive sites, the total of the site-specific mean beach

counts, and the size composition of the seals observed during the

counts (Fig. 1).

Since 1983, the number of pups born at the main reproductive

sites (excluding Midway Atoll) has been highly variable, and the

variability has been largely determined by the number born at

French Frigate Shoals (Fig. 1a), the largest subpopulation. In

1997, 201 pups were counted at these sites, 97 of which were born

at French Frigate Shoals. Mean beach counts, excluding pups,

from the main reproductive sites (again, excluding Midway Atoll)

totaled 373 seals and have remained essentially unchanged since

1993 (Fig. 1b).

Since the mid 1980s, adults have comprised a growing portion

of the animals counted (Fig. 1c) and, in 1997, the composition of

the counts remained largely skewed towards adults. This shift in

composition bodes poorly for reproduction in the near future if

older adult females are not replaced by young females reaching

reproductive age. The overall impact from this shift in

composition will be determined by the magnitude of its change and

the length of time that the resulting skewed distribution

persists, neither of which can be reliably predicted at this

time. High mortality of immature seals appears to be a major

factor leading to the shift in composition, particularly at

French Frigate Shoals and Laysan Island.

In 1997, three management activities were conducted by the

Marine Mammal Research Program (Honolulu Laboratory, National

Marine Fisheries Service) to enhance recovery of the species.

First, debris capable of entangling seals was removed from all
iv

Fig. 1. Demographic trends of the Hawaiian monk seal, based on

the main reproductive sites (excluding Midway Atoll). a) Number

of pups born. b) Total of mean beach counts, excluding pups. c)

Portion of the counts comprised of adults, subadults, and

juveniles.
v

study sites and 13 entangled seals were disentangled by field

biologists. Second, debris was removed from sections of fringing

reef at French Frigate Shoals and Pearl and Hermes Reef to reduce

hazards to the seals, assess the extent of reef fouling, and

determine the feasibility of large scale debris removal. Third,

weaned pups were translocated within French Frigate Shoals to

increase their probability of survival.

This document describes these and other field studies

conducted during 1997. The format followed is intended to

provide complete, standardized, and timely summaries of the

research activities and findings at each study site. The ready

availability of such information is essential for ongoing efforts

to stop the decline of this species and enhance its recovery.
vii

CONTENTS

Page

CHAPTER 1. GENERAL INTRODUCTION .............. 1

MATERIALS AND METHODS ................ 3

Censuses and Patrols .............. 3

Reproduction .................. 4

Factors Affecting Survival ........... 5

Individual Identification ............ 6

Measurements of Seals .............. 7

Collection of Samples .............. 8

CHAPTER 2. THE HAWAIIAN MONK SEAL ON

FRENCH FRIGATE SHOALS, 1997 ................ 9

RESEARCH . . . . . . . . . . . . . . . . . . . . . . . 11

Censuses and Patrols . . . . . . . . . . . . . . 11

Individual Identification . . . . . . . . . . . . 11

Collection of Samples . . . . . . . . . . . . . . 11

Special Studies . . . . . . . . . . . . . . . . . 12

Habitat Use Study . . . . . . . . . . . . . 12

Reef Fish and Habitat Assessment . . . . . . 12

Health and Disease Study . . . . . . . . . . 12

Translocation of Weaned Pups . . . . . . . . 12

Debris Removal from Fringing Reef . . . . . 12

RESULTS . . . . . . . . . . . . . . . . . . . . . . . 13

Population Abundance and Composition . . . . . . 13

Reproduction . . . . . . . . . . . . . . . . . . 13

Interatoll Movement . . . . . . . . . . . . . . . 13

Factors Affecting Survival . . . . . . . . . . . 13

ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . 14

TABLES . . . . . . . . . . . . . . . . . . . . . . . . 15

CHAPTER 3. THE HAWAIIAN MONK SEAL ON

LAYSAN ISLAND, 1997 . . . . . . . . . . . . . . . . . . . . 23

RESEARCH . . . . . . . . . . . . . . . . . . . . . . . 25

Censuses and Patrols . . . . . . . . . . . . . . 25

Individual Identification . . . . . . . . . . . . 25

Collection of Samples . . . . . . . . . . . . . . 26

Noteworthy Events . . . . . . . . . . . . . . . . 26

Translocated Adult Males . . . . . . . . . . 26

Oiled Seals . . . . . . . . . . . . . . . . 26

RESULTS . . . . . . . . . . . . . . . . . . . . . . . 26

Population Abundance and Composition . . . . . . 26

Reproduction . . . . . . . . . . . . . . . . . . 27

Interatoll Movement . . . . . . . . . . . . . . . 27

Factors Affecting Survival . . . . . . . . . . . 27

ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . 27

TABLES . . . . . . . . . . . . . . . . . . . . . . . . 29
(CONTENTS, continued)

Page

viii

CHAPTER 4. THE HAWAIIAN MONK SEAL ON

LISIANSKI ISLAND, 1997 . . . . . . . . . . . . . . . . . . 37

RESEARCH . . . . . . . . . . . . . . . . . . . . . . . 39

Censuses and Patrols . . . . . . . . . . . . . . 39

Individual Identification . . . . . . . . . . . . 39

Collection of Samples . . . . . . . . . . . . . . 39

Noteworthy Events . . . . . . . . . . . . . . . . 40

Mating Behavior . . . . . . . . . . . . . . 40

Oiled Wildlife . . . . . . . . . . . . . . . 40

RESULTS . . . . . . . . . . . . . . . . . . . . . . . 40

Population Abundance and Composition . . . . . . 40

Reproduction . . . . . . . . . . . . . . . . . . 41

Interatoll Movement . . . . . . . . . . . . . . . 41

Factors Affecting Survival . . . . . . . . . . . 41

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

TABLES . . . . . . . . . . . . . . . . . . . . . . . . 43

CHAPTER 5. THE HAWAIIAN MONK SEAL ON

PEARL AND HERMES REEF, 1997 . . . . . . . . . . . . . . . . 51

RESEARCH . . . . . . . . . . . . . . . . . . . . . . . 53

Censuses and Patrols . . . . . . . . . . . . . . 53

Individual Identification . . . . . . . . . . . . 53

Collection of Samples . . . . . . . . . . . . . . 53

Special Studies . . . . . . . . . . . . . . . . . 54

Habitat Use Study . . . . . . . . . . . . . 54

Debris Removal from Fringing Reef . . . . . 54

RESULTS . . . . . . . . . . . . . . . . . . . . . . . 54

Population Abundance and Composition . . . . . . 54

Reproduction . . . . . . . . . . . . . . . . . . 54

Interatoll Movement . . . . . . . . . . . . . . . 54

Factors Affecting Survival . . . . . . . . . . . 55

ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . 55

TABLES . . . . . . . . . . . . . . . . . . . . . . . . 57

CHAPTER 6. THE HAWAIIAN MONK SEAL ON

MIDWAY ATOLL, 1997 . . . . . . . . . . . . . . . . . . . . 65

RESEARCH . . . . . . . . . . . . . . . . . . . . . . . 67

Censuses and Patrols . . . . . . . . . . . . . . 67

Individual Identification . . . . . . . . . . . . 68

Collection of Samples . . . . . . . . . . . . . . 68

Special Studies . . . . . . . . . . . . . . . . . 68

Radio Telemetry of Immature Seals . . . . . 68

RESULTS . . . . . . . . . . . . . . . . . . . . . . . 68

Population Abundance and Composition . . . . . . 68

Reproduction . . . . . . . . . . . . . . . . . . 69

Interatoll Movement . . . . . . . . . . . . . . . 69

Factors Affecting Survival . . . . . . . . . . . 69

ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . 69

TABLES . . . . . . . . . . . . . . . . . . . . . . . . 71
(CONTENTS, continued)

Page

ix

CHAPTER 7. THE HAWAIIAN MONK SEAL ON

KURE ATOLL, 1997 . . . . . . . . . . . . . . . . . . . . . 79

RESEARCH . . . . . . . . . . . . . . . . . . . . . . . 81

Censuses and Patrols . . . . . . . . . . . . . . 81

Individual Identification . . . . . . . . . . . . 82

Collection of Samples . . . . . . . . . . . . . . 82

Special Studies . . . . . . . . . . . . . . . . . 82

Assessment of Photogrammetry as a Tool to

Estimate Body Size . . . . . . . . . . 82

RESULTS . . . . . . . . . . . . . . . . . . . . . . . 82

Population Abundance and Composition . . . . . . 82

Reproduction . . . . . . . . . . . . . . . . . . 82

Interatoll Movement . . . . . . . . . . . . . . . 83

Factors Affecting Survival . . . . . . . . . . . 83

ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . 83

TABLES . . . . . . . . . . . . . . . . . . . . . . . . 85

CHAPTER 8. THE HAWAIIAN MONK SEAL ON

NECKER ISLAND, 1997 . . . . . . . . . . . . . . . . . . . . 93

RESEARCH . . . . . . . . . . . . . . . . . . . . . . . 95

Censuses and Patrols . . . . . . . . . . . . . . 95

Individual Identification . . . . . . . . . . . . 95

Collection of Samples . . . . . . . . . . . . . . 95

RESULTS . . . . . . . . . . . . . . . . . . . . . . . 95

Population Abundance and Composition . . . . . . 95

Reproduction . . . . . . . . . . . . . . . . . . 96

Interatoll Movement . . . . . . . . . . . . . . . 96

Factors Affecting Survival . . . . . . . . . . . 96

ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . 96

TABLES . . . . . . . . . . . . . . . . . . . . . . . . 97

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . 101

APPENDIXES . . . . . . . . . . . . . . . . . . . . . . . . 105

Appendix A.--Reports summarizing annual field research

on the Hawaiian monk seal by the National Marine

Fisheries Service and collaborating scientists . 107

Appendix B.--Hawaiian monk seal census form and 1997

census form directions. . . . . . . . . . . . . . 113
CHAPTER 1. GENERAL INTRODUCTION

3

The endangered Hawaiian monk seal (Monachus schauinslandi)

hauls out and breeds in the Northwestern Hawaiian Islands, (NWHI,

Fig. 1.1). The National Marine Fisheries Service (NMFS) is the

lead agency responsible for the recovery of the Hawaiian monk

seal. Each year the Southwest Fisheries Science Center, Honolulu

Laboratory, NMFS Marine Mammal Research Program conducts studies

at the main breeding sites to provide information necessary to

evaluate (1) the status and trends of the monk seal populations,

(2) natural history traits such as survival, reproduction,

growth, behavior, and feeding habits, and (3) the success of

various activities designed to facilitate population growth.

The Marine Mammal Research Program began research on

Hawaiian monk seals at most major reproductive sites in the NWHI

during 1981 (Kure Atoll, Laysan Island, and Lisianski Island),

1982 (French Frigate Shoals (FFS) and Pearl and Hermes Reef), and

1983 (Midway Atoll). Nearly every year thereafter, field camps

of several days to 9 months were established to monitor and

enhance the recovery of this species. Limited population

monitoring has also been conducted at Nihoa and Necker Islands,

where pup production is spatially limited by availability of

haulout area. Reports summarizing past NMFS research are listed

in Appendix A.

In 1997, the Hawaiian monk seal research activities were to

(1) conduct beach counts (censuses), (2) tag weaned pups and

immature seals for permanent identification, (3) identify other

seals by previously applied tags and by natural or applied

markings, (4) monitor reproduction, survival, injuries,

entanglements, interatoll movements, disappearances, and deaths,

(5) perform necropsies, (6) collect scat and spew samples for

food habit analysis, (7) collect tissue samples for DNA analysis

of paternity patterns and genetic variation within and among

populations, and (8) inventory, sample, and destroy debris

capable of entangling seals. Location-specific objectives and

summaries of data collected during the 1997 field season are

described in the following chapters. Much of the information

presented in this memorandum is incorporated into larger data

sets for additional analysis and publication elsewhere.

MATERIALS AND METHODS

Censuses and Patrols

The primary means of data collection were censuses and

patrols. Censuses consisted of timed, standardized beach counts

during which an entire island or atoll was surveyed for seals.

Although data were collected on all seals, those that were in the

water, captive, or dead were excluded from the beach count

totals. Identified individuals were counted only once if they

were resighted during the survey. The resulting counts did not

reflect total population size but provided an index of population
4

size for comparison among years and locations. Data collected on

each seal observed during censuses included size class (ranging

from pup to juvenile, subadult, and adult size as described in

Stone, 1984); sex; location on the island; beach position

(indicating whether the seal was in the water or on land); body

condition (a subjective estimate; e.g., fat or thin);

identification information (permanent or temporary identification

numbers and tag numbers); molting status (an estimate of the

percentage an animal had molted); and disturbance index (the

extent that the observer disturbed the seal). Further data were

collected if any of the following events occurred: (1) factors

affecting survival (e.g., entanglements or mobbings), (2) animal

handling, (3) photography, and (4) documentation of tag condition

(e.g., good or broken). In addition, behavior data (seal

associations and interactions) were collected on Laysan and

Lisianski Islands. A sample census form and guidelines for its

completion are included in Appendix B. Censuses were conducted

once at Necker Island or every 3-8 days (at all other locations)

starting at 1300 Hawaii standard time when possible, using census

methods and criteria outlined in Johanos et al. (1987). Atollwide counts for locations with more than a single island (French

Frigate Shoals, Pearl and Hermes Reef, Midway Atoll, and Kure

Atoll) were completed within a 2-day period. The perimeter of

each study area was divided into sectors to facilitate the

analysis of data and detection of demographic trends in different

geographic areas. Census methods specific to each location are

detailed in the following chapters.

Patrols consisted of untimed surveys of an entire island

perimeter. Information collected during patrols was similar to

that collected during censuses. Because patrols were not timed,

observers concentrated on documenting adult and subadult

behavior, identifying and marking individuals, and collecting

scat samples. Island-specific standardized patrols were

conducted at some locations and are described in the following

chapters.

During all observation periods (i.e., censuses, patrols, and

incidental sightings), observers attempted to minimize seal

disturbance by walking above the beach crest and using vegetation

as a visual barrier. On census days, activities which could

disturb the animals and bias the count were not conducted until

after the count was completed. Additionally, special efforts

were directed towards the documentation of (1) births, pup

exchanges, and weanings, (2) mating activities, adult male

aggression, and post-mobbing aggregations (defined below), (3)

entanglements in marine debris, (4) injuries, and (5) deaths.

Reproduction

Parturient females were identified, and birth and weaning

information were recorded. Because parturient females will nurse
5

pups other than their own (Boness, 1990), efforts were made to

identify pups and document changes in nursing relationships from

birth to weaning. A pup exchange occurred when the pups of two

lactating females were switched. Most frequently, such exchanges

occurred during an aggressive interaction between the two

females. On other occasions, a mother and pup became separated,

and one or both seals then actively sought and obtained another

nursing relationship.

The average nursing period was calculated for the pups at

each location. The average lactation period of parturient

females was also calculated for seals at FFS because higher

population density and frequent pup exchanges (Boness, 1990) made

it difficult to track individual pups and determine their nursing

period. Nursing or lactation periods were defined as the number

of days from birth until the end of the last nursing

relationship. Temporary breaks in nursing relationships were not

subtracted from the total. When the exact birth or weaning date

was not known, but occurred within a range of 4 days or less,

then the midpoint of that range was used as the start or end date

for the calculation of the average nursing or lactation period.

Nursing or lactation data were not used if the range exceeded 4

days or if the pup died or disappeared before weaning.

Factors Affecting Survival

A wide range of injuries was observed. The origins of these

injuries were distinguished based upon characteristic wound

patterns described in Hiruki et al. (1993). Injuries were

documented if they were related to mounting or entanglement or if

they were considered severe enough to possibly affect survival.

Injuries were considered severe, and were summarized, if they

consisted of (1) three or more abscesses, each <5 cm in diameter,

or one abscess with a diameter 5 cm; (2) an amputation of more

than one digit (either foreflipper or hindflipper); (3) at least

three punctures or gaping wounds, if largest dimension was <5 cm,

or one gaping wound with a maximum diameter-largest dimension 5

cm; or (4) densely spaced (overlapping) scratches, abrasions, or

lacerations covering an area equivalent to half the dorsum, or

evidence of extensive underlying tissue damage (e.g., an uneven

or darkened surface of the injured area, leaching fluids, or

impaired seal movement). We did not include injuries that were

healed when first observed.

A seal was listed as dead if its death or carcass was

observed. Deaths summarized here include carcasses found at the

beginning of the field season if the seal had clearly died during

the calendar year. A seal was listed as probably dead if it

sustained severe injuries or was emaciated (with skeletal

structure clearly evident) and subsequently disappeared. In

addition, one of the following conditions must have been

satisfied to place a seal in the "probably dead" category:
6

1

Reference to trade names does not imply endorsement by the

National Marine Fisheries Service, NOAA.

(1) the seal was lethargic, had difficulty moving, or floated

listlessly in the water, and disappeared more than a week before

the end of data collection, or (2) the seal was in deteriorating

condition (loss of weight, enlargement of abscesses, sloughing of

skin) and disappeared at least 10 surveys or 1 month before the

end of data collection (whichever was longer). Nursing pups were

listed as probably dead if they disappeared within 3 weeks of

birth.

Mobbing and other mating-related male aggressions were

observed and recorded. By definition, mobbing occurred when

multiple males attempted to mate with a single seal, usually an

adult female or immature seal of either sex, causing injury or

death of that seal (e.g., Alcorn, 1984). Mating-related

aggression was defined as any incident where an adult or subadult

male repeatedly bit the dorsum, attempted to mount, and tried to

prevent the escape of another seal. These incidents were

summarized in this report if they simultaneously involved more

than one male aggressor or resulted in at least one puncture or

gaping wound (missing skin or extending into the blubber layer)

or >15 scratches to the dorsum or flanks. Post-mobbing

aggregations were also summarized: these were groups of males

congregated on the beach, attending a seal with new mounting

injuries as described above.

Individual Identification

During censuses and patrols, individual seals were

identified by tags, applied bleach marks, scars, or natural

markings. After weaning, all pups were tagged on each hind

flipper with a colored plastic Temple Tag, ®1 uniquely coded to

indicate island or atoll population, year of birth, and

individual ID (Gilmartin et al., 1986). In addition, passive

integrated transponder (PIT) tags were implanted subcutaneously

in the dorsum of each weaned pup (two each at FFS and one each at

other locations) (see Lombard et al., 1994, for detailed tagging

procedures).

Colored plastic Temple Tags have been applied to nearly all

weaned pups since 1981 at Kure Atoll, 1982 at Lisianski Island,

1983 at Laysan Island and Pearl and Hermes Reef, 1984 at French

Frigate Shoals, and 1995 at Midway Atoll. Pups at Midway Atoll,

Necker and Nihoa Islands, and the main Hawaiian Islands have been

tagged opportunistically since 1983. Since 1991, PIT tags have

also been implanted subcutaneously in the dorsum of most weaned

pups.
7

In 1997, untagged immature seals were tagged with Temple

Tags uniquely coded to indicate that their ages and birth

locations were unknown. Immature seals with lost or broken tags

were retagged to maintain their identities.

At five locations (Laysan Island, Lisianski Island, Pearl

and Hermes Reef, Midway Island, and Kure Atoll), seals were

bleach-marked for individual identification (Stone, 1984), using

the solution described in Johanos et al. (1987). Molting seals

were re-marked to maintain their identities. At Laysan and

Lisianski Islands, nursing pups were also bleached prior to molt.

Tags, scars, natural markings, and any applied bleach marks

were sketched on an individual scar card, which was revised

throughout the field season to maintain a current description of

the identifying marks of each seal. Photographs of scars and

natural markings were added to individual identification files

begun during 1981 or 1982.

Population size and composition were determined at locations

where all seals were identified; partial composition was

determined where all seals within certain size and sex classes

were identified. These statistics included all individuals seen

alive at the location during the interval from March through

August and all pups born during the year. Captive seals were

included if they were released in the current year. If a seal

was seen at more than one location during March-August, it was

included in the population where it was sighted closest to May 15

unless it pupped or molted at another location. A parturient

female was always included in the population where it pupped, and

a non-parturient seal was included in the population where it

molted. Pups were always included in the population where they

were born.

The movement of seals between island or atoll populations

confounds the estimation of population size and composition when

the study period is short (i.e., less than 1 month). This is

particularly true at Midway Atoll, where a number of the observed

seals were tagged at other locations (primarily Kure Atoll and

Pearl and Hermes Reef). These seals may be transient visitors,

and additional study is needed to distinguish them from seals

that reside at Midway Atoll.

Measurements of Seals

Pups were measured to determine their condition, growth

patterns, and the relation between size and survival.

Measurements were taken as soon after weaning as possible and

included straight dorsal length (Winchell, 1990) and axillary

girth (American Society of Mammalogists, 1967).
8

Collection of Samples

Samples were collected for DNA analysis, pathology analysis,

investigation of food habits, and documentation of marine debris.

Tissue samples for DNA analysis were collected during tagging

efforts for all newly tagged or retagged seals and during

necropsies on recently dead seals. Samples of sloughed epidermis

and fur from molting seals were also collected at Laysan Island

on an opportunistic basis for DNA analysis. The primary

objectives of genetic analyses are to investigate paternity

patterns and determine genetic variability within and among

populations.

For each dead seal recovered, an external examination was

made, photographs were taken, and external measurements and

observations were recorded. For a recent death, an internal

examination was made, and samples of tissue, organs, parasites,

and stomach contents were collected. Detailed descriptions of

necropsy procedures and sample collection methods are in Winchell

(1990).

Scat and spew samples were collected (Alcorn, 1984) for

analysis of food habits. Emphasis was placed on collecting these

samples from seals of known size and sex class, but samples from

seals of unknown size and sex class were also collected.

Nets, lines, ropes, and other debris capable of entangling

seals and turtles were inventoried and destroyed, following the

methods in Johanos and Kam (1986).
CHAPTER 2. THE HAWAIIAN MONK SEAL ON

FRENCH FRIGATE SHOALS, 1997

Mitchell P. Craig and Melissa A. Shaw

11

The largest island population of Hawaiian monk seals is

located at French Frigate Shoals (FFS, lat. 23°45'N, long.

166°10'W), ca. 830 km northwest of Oahu in the Northwestern

Hawaiian Islands. This atoll is part of the Hawaiian Islands

National Wildlife Refuge (Fig. 1.1) and consists of 10 permanent

islands and 7 semipermanent sand spits (Fig. 2.1).

RESEARCH

The National Marine Fisheries Service (NMFS) began research

on Hawaiian monk seals at FFS in 1982. In 1997, research was

conducted by NMFS during January 8-23 and March 8-September 13.

Incidental observations were recorded by U.S. Fish and Wildlife

Service (USFWS) personnel during the rest of the year. The

perimeters of the six larger islands were divided into sectors

using artificial or natural landmarks. Research activities

specific to this population in 1997 included (1) investigation of

habitat use patterns using satellite-linked telemetry and sealmounted video cameras, (2) assessment of nearshore prey

availability and habitat structure, (3) collection of blood

samples for health and disease studies, (4) translocation of

weaned pups within the atoll to increase survival, and (5) debris

removal from the fringing reef.

Censuses and Patrols

Atoll censuses (n = 10) were conducted every 8 days, on

average, from May 20 to August 5. Each atoll census began

between 0955 and 1113 Hawaii standard time and ended between 1550

and 1800. All islands were usually censused on foot by one or

two persons. Patrols were conducted on noncensus days to monitor

pupping activity and factors affecting survival.

Individual Identification

A total of 443 individuals (346 excluding pups) were

identified by existing or applied tags, scars, or natural

markings. Most weaned pups (n = 51) were tagged with Temple

Tags; 46 of these same pups were tagged with passive integrated

transponder (PIT) tags. Two juvenile seals (one male and one

female) born in 1996 were tagged with Temple Tags in January

1997. One subadult male and one adult male were retagged with

Temple Tags.

Collection of Samples

Fifty scat samples were collected and processed. Tissue

samples were collected from 38 seals during tagging. Necropsies

were performed on nine dead seals and two fetuses found at the

study site, and tissue samples were collected.
12

Special Studies

Habitat Use Study

In January 1997, four satellite-linked time-depth recorders

were retrieved from two adult males and two adult females that

were instrumented in October 1996 as part of a foraging study

conducted in collaboration with the University of Minnesota.

Although another instrumented adult female was located, the unit

was not retrieved because this seal was determined to be

pregnant. In March, eight additional seals (three adult males

and five adult females) were instrumented with satellite-linked

time-depth recorders. Four of these recorders were retrieved in

July (from three adult males and one adult female). Two of the

adult females instrumented in October 1996 pupped successfully in

1997. None of the adult females instrumented in March pupped in

1997. Only females not considered to be pregnant were

instrumented with satellite-linked time-depth recorders. In July

and August, 10 adult male seals were instrumented with video

cameras which were retrieved in 4 to 31 days. Nineteen seals

were measured (axillary girth and dorsal straight length) during

instrument applications and removals.

Reef Fish and Habitat Assessment

In July and August, the Ecosystem and Environment

Investigation of the Honolulu Laboratory, NMFS, continued ongoing

habitat assessment. This included a reef fish survey and video

camera transects around and within the atoll and at Brooks Banks.

Health and Disease Study

Blood samples were collected from 31 seals as part of a

health survey of the wild population; samples were collected

during all satellite tag applications and retrievals and all

video camera applications and retrievals but one.

Translocation of Weaned Pups

In response to unusually high mortality of pups at Trig

Islet and Whale-Skate, intensive monitoring of mother-pup pairs

and newly weaned pups was initiated. Circumstantial and direct

evidence implicated both sharks and adult males in the loss of

pups at these locations. Fourteen weaned pups (seven males and

seven females) were translocated from Trig and Whale-Skate to the

Gins to increase their probability of survival.

Debris Removal from Fringing Reef

Personnel aboard the NOAA ship Townsend Cromwell removed

debris from a section of fringing reef to reduce these hazards to

monk seals and other marine life, assess the extent of reef
13

fouling, and determine the feasibility of a large scale debris

removal effort. During this effort, a partially submerged net

was found near Whaleskate with two immature seals entangled in

it; one seal had recently drowned and the other was released

alive.

RESULTS

Population Abundance and Composition

The means (±SD) for 10 atoll censuses were 144.7 seals

(±13.2) including pups, and 111.3 seals (±12.1) excluding pups

(Table 2.1). The total spring-summer population included 161

immature individuals (subadults, juveniles, and pups), of which

64 were subadults or juveniles (Table 2.2). Although the total

numbers of adult males and females were not obtained due to our

inability to identify all individuals, it is estimated that less

than 5 adult females and 10 adult males remained unidentified at

the end of the field season. The numbers of tagged known-age

seals born at FFS during the period from 1984 to 1996 and

resighted there in 1997 are summarized in Table 2.3.

Reproduction

At least 97 pups were born: 59 were weaned, 36 died or

disappeared prior to weaning, and the weaning status of 2 pups

was unknown (Table 2.4a). Two fetuses were found, but not

counted in the total number of pups born. Nursing periods and

measurements of weaned pups are summarized in Table 2.4b. A

total of 166 adult-sized females were identified and 92 (55.4%)

of those were parturient. The birth rate was 57.6% (57/99) for

older (>13 years old) and unknown-age adult females and 52.2%

(35/67) for younger females of adult size ( 13 years old).

Parturient females were more likely to be identified during

lactation, which probably biased the estimates of birth rate

upward. As noted above, our best estimate is that less than five

adult-sized females remained unidentified at FFS. The mean (±SD)

lactation period for 23 females was 37.0 d (±5.8 d). At least 17

pups were fostered by mothers other than their own.

Interatoll Movement

Interatoll movement was documented for seven seals that made

a total of seven movements between FFS and either Necker Island,

Gardner Pinnacles, or Laysan Island (Tables 2.5a and b).

Factors Affecting Survival

Attacks by large sharks, mounting attempts by males,

entanglement, and other/unknown factors resulted in 74 lifethreatening conditions, which led to the confirmed deaths of 16

animals and the probable deaths of 28 seals (Table 2.6). A
14

nursing pup was eaten by a shark during an observed attack. At

least three seals were entangled; in addition to the two seals

found entangled in the same partially submerged net, a third

seal, entangled in a net on shore, was released by USFWS

personnel. In addition to the deaths presented in Table 2.6, two

aborted fetuses were found on Tern Island in January, 1997.

ACKNOWLEDGMENTS

We acknowledge the support of the U.S. Fish and Wildlife

Service, Hawaiian Islands National Wildlife Refuge staff. We

thank the captain, officers, and crew of the NOAA ship

Townsend Cromwell for logistical assistance.
TABLES
17

Table 2.1.--Summary statistics for atoll censuses ( n = 10) of

Hawaiian monk seals at French Frigate Shoals from

May 20 to August 5, 1997.

Size/Sex

Mean number of

individuals

Standard

deviation

Adults 94.7 11.0

Male 33.2 5.1

Female 58.0 8.3

Unknown 3.5 1.6

Subadults 7.8 2.1

Male 2.4 2.0

Female 4.4 1.5

Unknown 1.0 1.3

Juveniles 8.8 3.6

Male 4.9 3.0

Female 3.2 0.6

Unknown 0.7 0.8

Pups 33.4 3.2

Male 11.2 2.3

Female 7.0 1.9

Unknown 15.2 3.3

Nonpup Total 111.3 12.1

Grand Total 144.7 13.2
18

Table 2.2.--Composition of the Hawaiian monk seal population at

French Frigate Shoals during the spring and summer of

1997. Includes all pups born during the calendar

year.

Number of seals

Size Male Female Unknown Total

Sex ratio

male:female

Adults 116a 166a 0 282a 0.7:1

Subadults 11 18 0 29 0.6:1

Juveniles 18b 17b 0 35b 1.1:1

Pups 54 31 12 97 1.7:1

Nonpup Total 145a 201a 0 346a 0.7:1

Grand Total 199a 232a 12 443a 0.9:1

a

Although the adult population was not totally identified, it is

estimated that less than 5 adult females and 10 adult males

remained unidentified at the end of the field season.

b

Numbers exclude six males and six females that were seen in

January, but not resighted subsequently. Numbers include 2

males and 3 females that were last observed in March.
19

Table 2.3.--Summary of tagged known-age seals born at French

Frigate Shoals and resighted there in 1997.

Age

(years) Sex

Number originally

tagged

Number resighted

in 1997

13 Male

Female

49

43

10

15

12 Male

Female

48

38

5

15

11 Male

Female

52

48

9

15

10 Male

Female

55

51

13

15

9 Male

Female

52

62

5

8

8 Male

Female

51

50

7

5

7 Male

Female

39

40

1

2

6 Male

Female

24

44

1

3

5 Male

Female

36

55

2

7

4 Male

Female

40

39

6

2

3 Male

Female

47

48

1

4

2 Male

Female

29

26

6

5

1 Male

Female

39

30

17

15
20

Table 2.4a.--Summary of Hawaiian monk seals born at French

Frigate Shoals in 1997.

Event

Number of pups

Male Female Unknown Total

Born 54 31 12 97a

Died/probably died

prior to weaning

19 6 11 36

Weaning status unknown 0 1 1 2b

Weaned 35 24b 0 59c

Tagged 32 19 0 51

a

Two fetuses (1 male and 1 female) were also found but are

not included in the total number of pups born.

b

Three nursing pups were observed in October and November; 1

pup weaned and the fate of the other two pups was unknown.

c

Two female weaned pups died prior to tagging, and six weaned

pups (3 males and 3 females) remained untagged.

Table 2.4b.--Summary of nursing periods and measurements of

weaned pups at French Frigate Shoals in 1997.

Nursing periods were calculated where both birth and

weaning date ranges were 4 days. All measurements

were taken within 2 weeks after weaning.

Nursing period

(d)

Axillary

girth (cm)

Straight dorsal

length (cm)

Mean 39.6 101.8 126.4

St. Dev. 2.5 10.8 7.2

n 4 42 34
21

Table 2.5a.--Known movement of Hawaiian monk seals to French

Frigate Shoals from other locations in 1997,

summarized by movements between two locations. No

seals made more than one trip.

Original location Number, size, and sex class

Gardner Pinnacles 1 adult male

Laysan Island 1 adult male,

2 adult females,

1 subadult male

Table 2.5b.--Known movement of Hawaiian monk seals from French

Frigate Shoals to other locations in 1997,

summarized by movements between two locations. No

seals made more than one trip.

Destination Number, size, and sex class

Necker Island 1 adult female

Laysan Island 1 adult female
22

Table 2.6.--Factors affecting Hawaiian monk seal survival at

French Frigate Shoals in 1997.

Outcome

Size Sex Total Injured Died Probably died

Attack by Large Shark

Adult Male

Female

5

8

5

8

0

0

0

0

Subadult Male 2 2 0 0

Juvenile Male 1 1 0 0

Weaned pup Female 1 0 1 0

Nursing pup Unknown 2 1a 1b 0

Mounting by Males

Adult Female 3 3 0 0

Weaned pup Male

Female

5

4

4c

2

1

2

0

0

Nursing pup Male

Female

3

2

0

0

3

2

0

0

Entanglement

Adult Female 1d 00 0

Subadult Male 1e 01 0

Juvenile Male 1e 00 0

Other/Unknown

Adult Male 2 2 0 0

Weaned pup Male 3 0 2 1

Nursing pup Male

Female

Unknown

16

4

10

0

0

0

1

2

0

15

2

10

a

Disappeared later of unknown causes.

b

Pup was eaten by a shark during an observed attack.

c

One seal was mounted on two different occasions.

d

Seal released by observers (net partially removed, came off as

seal entered water).

e

Two seals were found entangled in the same net; one had drowned,

and the other was released by observers.
CHAPTER 3. THE HAWAIIAN MONK SEAL ON

LAYSAN ISLAND, 1997

Brenda L. Becker and Amber D. Pairis

25

Laysan Island (lat. 25°42'N, long. 171°44'W) is located ca.

1,300 km northwest of Oahu in the Northwestern Hawaiian Islands

(Fig. 1.1). This island lies within the Hawaiian Islands

National Wildlife Refuge and is one of the major haulout and

pupping locations of the Hawaiian monk seal.

RESEARCH

The National Marine Fisheries Service (NMFS) began research

on Hawaiian monk seals at Laysan Island in 1981. In 1997,

research was conducted by NMFS during March 12-July 24, and

incidental observations were recorded by U.S. Fish and Wildlife

Service (USFWS) personnel during the rest of the year. The

perimeter of the island (ca. 11 km) was divided into 20 sectors

using artificial or natural landmarks (Fig. 3.1). Research

objectives specific to this population in 1997 included

identification of all seals, assessment of maternity and pup

exchanges, comparison of three methods to measure length of

weaned pups, assessment of the prevalence of eye ailments in the

wild population, description of male behavioral patterns and

aggression to determine if the removal of 22 adult males from

Laysan Island in 1994 reduced the incidence of mobbing, and

identification of any of those males that may have returned to

Laysan after translocation to the main Hawaiian Islands.

Censuses and Patrols

Censuses and patrols were scheduled to ensure that the

entire island perimeter was monitored at least once each day

during March 24-July 21. Censuses (n = 20) were conducted by two

observers every fourth day from April 7 to June 25. Each census

began at 1300 Hawaii standard time and continued for 3.0 to 4.1

hours.

Standardized behavior patrols were conducted on 43

noncensus days from March 24 to June 21 to assess activity

patterns of adults and large subadults, document male aggression,

and detect mobbing incidents. During behavior patrols, attention

was directed out to sea as much as possible because mobbings have

been observed most frequently in the water. Forty-two fullisland incidental patrols to record noteworthy events were

conducted on noncensus and nonbehavior patrol days.

Individual Identification

A total of 270 individuals (233 excluding pups) were

identified by existing or applied tags, bleach marks, scars, or

natural markings. Bleach marks were applied to 231 seals,

including 36 nursing pups. All weaned pups ( n = 35) were tagged

with Temple Tags and passive integrated transponder (PIT) tags.

One pup, which weaned after the NMFS camp ended, was bleachmarked for identification in 1997 and tagged in 1998.
26

Collection of Samples

Ninety-nine scat and 48 spew samples were collected.

Tissue samples were collected from 34 weaned pups during tagging.

One necropsy was performed, and tissue samples and skull were

collected. A lower jaw and os penis were collected from a seal

that died during a previous year. Molt samples from 47 seals and

sloughed fur from an injured seal were collected. Eleven

placentas were also collected. In total, 713 pieces of

potentially entangling debris were inventoried and destroyed,

with the exception of 7 items: 4 were removed and collected from

an entangled animal (2 from a seal and 2 from a seabird); 1 was

left in place (where it would not pose a hazard); and 2 were

collected for further analysis.

Noteworthy Events

Translocated Adult Males

Twenty-two adult male seals were collected from Laysan

Island in 1994; 1 male died shortly after capture and the

remaining 21 males were translocated to the main Hawaiian

Islands. None of the translocated males had migrated back to

Laysan Island, nor were they seen elsewhere in the Northwestern

Hawaiian Islands in 1997, though one was sighted at Nihoa Island

in 1996.

Oiled Seals

Eleven of seventeen seals observed with oiled pelage on

Laysan Island in the spring of 1993 were sighted there in 1997.

These seals appeared to be in good health, but sublethal or longterm effects could not be evaluated. Of the six not sighted in

1997, one seal was last seen in 1995, four were last seen in 1994

(one of these, an adult male, was translocated to the main

Hawaiian Islands in 1994), and one was last seen in 1993.

RESULTS

Population Abundance and Composition

The means (±SD) for 20 censuses were 101.9 seals (±15.7)

including pups, and 84.8 seals (±9.0) excluding pups (Table 3.1).

The total spring-summer population was 263 individuals, 226

excluding pups (Table 3.2). The sex ratios of nonpup immature

seals and adults were ca. 1.0:1 (43 males:45 females) and 0.9:1

(65 males:73 females), respectively. The sex ratio for older

(>14 years of age) and unknown aged adults was slightly skewed

toward males at ca. 1.2:1 (38 males: 32 females), whereas the

ratio for younger adults (14 years of age) was ca. 0.6:1 (27

males:41 females). The numbers of tagged known-age seals born at
27

Laysan Island during the period from 1983 to 1996 and resighted

there in 1997 are summarized in Table 3.3.

Reproduction

At least 37 pups were born: 35 were weaned, 1 died prior to

weaning, and 1 was still nursing at the end of the NMFS camp

(Table 3.4a). Nursing periods and measurements of weaned pups

are summarized in Table 3.4b. Thirty-seven of seventy-three

(51%) adult-sized females were parturient. At least 14 pup

exchanges occurred between 12 nursing females; none of these

incidents were observed. Two births and one weaning event were

observed. One unusual temporary weaning (i.e., a nursing female

abandoned her pup and then returned) was documented. One female

had started to molt at the time of parturition and one parturient

female had an unusually enlarged nipple for several months

postweaning.

Interatoll Movement

Interatoll movement was documented for 14 seals that made a

total of 18 movements between Laysan Island and either French

Frigate Shoals or Lisianski Island (Tables 3.5a and b).

Factors Affecting Survival

Attacks by large sharks, mounting attempts by males,

entanglement, and other factors led to 19 life-threatening

conditions, which resulted in the confirmed death of 1 animal

(Table 3.6). No incidents of adult male aggression were

observed, and no seals were known to have died or disappeared

following male-mounting incidents. Five entanglements were

documented: in two incidents the seal escaped independently, and

in the other three the seal was released by observers. In

addition to the factors affecting survival presented in Table

3.6, the placenta was severed from two newborn pups whose

movement (and thus survival) was severely restricted by the

trailing tissue; two pups that nursed only 25 and 26 days each,

as a result of pup exchanges, were emaciated at the end of the

field camp and are not expected to survive the year; and a male

seal had a cyst or tumor, first observed in 1996, still evident

in 1997.

ACKNOWLEDGMENTS

We acknowledge the support of the U.S. Fish and Wildlife

Service, Hawaiian Islands National Wildlife Refuge staff and

thank the captain and crew members of the NOAA ship Townsend

Cromwell. Special thanks are extended to Rebecca Bernard,

Monette Boswell, Chris Depkin, Catherine McMahon, Elizabeth

Mitchell, Hadie Muller, Vanessa Pepi, Mari von Hoffman, and Peter

Winch for their data collection and seal bleaching assistance.
TABLES
31

Table 3.1.--Summary statistics for censuses ( n = 20) of Hawaiian

monk seals at Laysan Island from April 7 to June 25,

1997.

Size/Sex

Mean number of

individuals

Standard

deviation

Adults 47.0 6.9

Male 19.5 5.2

Female 27.2 7.9

Unknown 0.3 0.7

Subadults 17.0 5.6

Male 7.9 3.1

Female 8.9 3.7

Unknown 0.1 0.3

Juveniles 20.9 4.6

Male 10.4 2.9

Female 10.2 3.0

Unknown 0.3 0.4

Pups 17.1 9.1

Male 10.0 5.8

Female 7.2 3.5

Unknown 0.0 0.0

Nonpup Total 84.8 9.0

Grand Total 101.9 15.7
32

Table 3.2.--Composition of the Hawaiian monk seal population at

Laysan Island during the spring and summer of 1997.

Includes all pups born during the calendar year.

Number of seals

Size Male Female Unknown Total

Sex ratio

male:female

Adults 65 73 0 138 0.9:1

Subadults 19 21 0 40 0.9:1

Juveniles 24 24 0 48 1.0:1

Pups 19 17a 1 37 1.1:1

Nonpup Total 108 118 0 226 0.9:1

Grand Total 127 135 1 263 0.9:1

a

One neonatal pup death.
33

Table 3.3.--Summary of tagged known-age seals born at Laysan

Island and resighted there in 1997.

Age

(years) Sex

Number originally

tagged

Number resighted

in 1997

14 Male

Female

10

10

1

6

13 Male

Female

16

13

2

5

12 Male

Female

16

14

1

5

11 Male

Female

15

17

2

2

10 Male

Female

13

15

3

5

9 Male

Female

23

17

4

3

8 Male

Female

16

13

2

2

7 Male

Female

7

9

2

3

6 Male

Female

18

13

8

8

5 Male

Female

18

14

2

3

4 Male

Female

23

14

4

4

3 Male

Female

18

29

8

10

2 Male

Female

16

21

8

11

1 Male

Female

23

21

16

14
34

Table 3.4a.--Summary of Hawaiian monk seals born at Laysan Island

in 1997.

Event

Number of pups

Male Female Unknown Total

Born 19 17 1 37

Died prior to weaning 0 1 0 1

Still nursing 0 0 1 1

Weaned 19 16 0 35

Tagged 19 16a 0 35

a

Includes one pup weaned and bleached after the NMFS camp ended

in 1997, and tagged in 1998.

Table 3.4b.--Summary of nursing periods and measurements of

weaned pups at Laysan Island in 1997. Nursing

periods were calculated where both birth and weaning

date ranges were 4 days. All measurements were

taken within 2 weeks after weaning.

Nursing period

(d)

Axillary

girth (cm)

Straight dorsal

length (cm)

Mean 37.0 103.7 125.8

St. Dev. 6.7 10.6 7.0

n 35 34 34
35

Table 3.5a.--Known movement of Hawaiian monk seals to Laysan

Island from other locations in 1997, summarized by

movements between two locations. No seals made more

than one trip.

Original location Number, size, and sex class

French Frigate Shoals 1 adult female

Lisianski Island 1 adult male,

6 adult females,

2 subadult females

Table 3.5b.--Known movement of Hawaiian monk seals from Laysan

Island to other locations in 1997, summarized by

movements between two locations. No seals made more

than one trip.

Destination Number, size, and sex class

French Frigate Shoals 1 adult male,

2 adult females,

1 subadult male

Lisianski Island 3 adult females,

1 subadult female
36

Table 3.6.--Factors affecting Hawaiian monk seal survival at

Laysan Island in 1997.

Outcome

Size Sex Total Injured Died Probably died

Attack by Large Shark

Subadult Male 1 1 0 0

Juvenile Male

Female

2

2a 2

2

0

0

0

0

Mounting by Males

Adult Female 3 3 0 0

Entanglement

Adult Female 1b 00 0

Juvenile Female 1c 00 0

Weaned pup Male 2d 00 0

Unknown Unknown 1e 00 0

Other

Adult Female 1 1 0 0

Juvenile Male

Female

2

1

2

1

0

0

0

0

Weaned pup Male 1 1 0 0

Nursing pup Female 1f 01 0 a

Seal has an opacity in one eye from 1996, uncertain if vision is

affected.

b

Seal was released by observer.

c

Seal escaped by itself.

d

One seal became entangled twice and was released by observers

each time.

e

Entangling debris was dragged by a seal from beach berm down

towards waterline, but animal was not observed (only tracks);

unknown if animal was injured.

f

Pup was blind and small, and mother of pup was severely injured

during a mobbing event several days prior to parturition.
CHAPTER 4. THE HAWAIIAN MONK SEAL ON

LISIANSKI ISLAND, 1997

Hannahrose M. Nevins, Joshua Adams and Matthew R. Rutishauser

39

Lisianski Island (lat. 26°02'N, long. 174°00'W) is one of

the major haulout and pupping locations of the Hawaiian monk

seal. The island is located ca. 1,760 km northwest of Oahu (Fig.

1.1) and is part of Neva Shoals, a shallow reef bank within the

Hawaiian Islands National Wildlife Refuge.

RESEARCH

The National Marine Fisheries Service (NMFS) began research

on Hawaiian monk seals at Lisianski Island in 1981. In 1997,

research was conducted by NMFS during March 10-July 1. The

perimeter of the island (ca. 5.2 km) was divided into 20 sectors

using artificial or natural landmarks (Fig. 4.1). Research

objectives specific to this population in 1997 included

identification of all seals, assessment of maternity and pup

exchanges, and documentation of adult male behavioral patterns

and aggression.

Censuses and Patrols

Censuses and patrols were scheduled to ensure that the

entire island was monitored at least once each day during

March 15-July 1. Censuses (n = 18) were conducted by two

observers every fifth day from March 31 to June 24, beginning at

1300 Hawaii standard time and continuing for 1.4-2.6 hours.

Standardized behavior patrols were conducted on noncensus

days to assess activity patterns of adults and large subadults,

document male aggression, and detect mobbing incidents. During

these patrols (n = 73), attention was directed out to sea as much

as possible because mobbing has been observed most frequently in

the water.

Individual Identification

A total of 189 individuals (167 excluding pups) were

identified by existing or applied tags, bleach marks, scars, or

natural markings. All weaned pups (n = 19) were tagged with

Temple Tags and passive integrated transponder (PIT) tags. One

Temple Tag was reapplied on a weaned pup that had broken its

original tag. Two adult male seals were retagged with Temple

Tags.

Collection of Samples

One hundred and four scat and 22 spew samples were

collected. Tissue samples were collected from 21 seals during

tagging. Necropsies were performed and tissue samples were

collected from three dead seals, including two adult males and

one female neonate pup. Skeletal samples were collected from

four seals: two skulls from previous mortalities and two skulls
40

from adult males necropsied this season. In total, 417 pieces of

potentially entangling debris were inventoried and destroyed.

Noteworthy Events

Mating Behavior

Two adults were observed possibly mating in shallow water.

The male clasped the female with his left foreflipper while

holding onto her back with his teeth. The male's posterior was

flexed and curved under the female's posterior end. They

maintained this position, slowly rolling in the shallows for

approximately 1 minute. In a separate incident, an adult male

was observed offshore over the reef, harassing an adult female

who had recently (<24 hours) weaned her pup. The male pursued

the female to the outer reef where they disappeared.

Oiled Wildlife

Beginning May 8 we observed oiled seabirds with as much as

50% of their plumage fouled. Approximately 20 birds, mostly

Masked and Red-Footed Boobies, were affected. A few Black

Noodies were also oiled. Six weaned pups and one adult male seal

were documented with oil spots on their pelage. The oiling

appeared superficial and did not seem to affect the seals'

health. No seabird mortality related to oiling was observed

during the study period.

RESULTS

Population Abundance and Composition

The means (±SD) for 18 censuses were 71.2 seals (±10.5)

including pups, and 57.3 seals (±10.3) excluding pups (Table

4.1). The total spring-summer population was 188 individuals,

166 excluding pups (Table 4.2). The sex ratios of nonpup

immatures and adults were ca. 1.0:1 (26 males:26 females) and

1.5:1 (69 males:45 females), respectively. The sex ratio for

older (>15 years of age) and unknown aged adults was skewed

toward males at ca. 2.6:1 (41 males:16 females), whereas the

ratio for younger adults (15 years of age) was ca. 1.0:1 (28

males:29 females). The numbers of tagged known-age seals born at

Lisianski Island during the period from 1982 to 1996 and

resighted there in 1997 are summarized in Table 4.3.
41

Reproduction

At least 22 pups were born: 19 were weaned, 1 died prior to

weaning, and 2 were nursing at the end of this study (Table

4.4a). Nursing periods and measurements of weaned pups are

summarized in Table 4.4b. Twenty-two of forty-five (49%) adultsized females were parturient. At least 31 pup exchanges

occurred between 9 nursing females; researchers observed 4 of

these incidents. One female nursed two pups at one time and a

second female fostered three pups simultaneously.

Interatoll Movement

Interatoll movement was documented for 12 seals that made a

total of 17 movements between Lisianski Island and either Laysan

Island or Pearl and Hermes Reef (Tables 4.5a and b).

Factors Affecting Survival

Attacks by large sharks, mounting attempts by males,

entanglement, emaciation, and other/unknown factors led to 18

life-threatening conditions, which resulted in the confirmed

deaths of 3 animals and the probable death of 1 seal (Table 4.6).

Six adult males were observed attempting to mount each other and

an adult female who sustained no apparent external injuries. One

adult male seal sustained a dorsal injury possibly associated

with male mounting. No seals were known to have died or

disappeared following male-mounting injuries. Three

entanglements were documented; in all incidents the seal was

released uninjured by observers. Two emaciated adult males died

during this study. In addition to the deaths presented in Table

4.6, the mummified carcass of a juvenile female was found at the

beginning of the field season; this seal died of unknown causes

after the 1996 field season.

ACKNOWLEDGMENTS

We acknowledge the support of the U.S. Fish and Wildlife

Service, Hawaiian Islands National Wildlife Refuge staff. We

thank the captain, officers and crew of the NOAA ship Townsend

Cromwell for logistical assistance.
TABLES
45

Table 4.1.--Summary statistics for censuses ( n = 18) of Hawaiian

monk seals at Lisianski Island from March 31 to

June 24, 1997.

Size/Sex

Mean number of

individuals

Standard

deviation

Adults 42.0 7.3

Male 24.4 6.2

Female 17.3 2.8

Unknown 0.3 0.6

Subadults 11.1 4.4

Male 6.3 3.3

Female 4.8 2.2

Unknown 0.0 0.0

Juveniles 4.2 1.6

Male 2.4 1.0

Female 1.7 1.1

Unknown 0.0 0.0

Pups 13.9 2.8

Male 6.8 1.8

Female 6.8 1.5

Unknown 0.3 0.6

Nonpup Total 57.3 10.3

Grand Total 71.2 10.5
46

Table 4.2.--Composition of the Hawaiian monk seal population at

Lisianski Island during the spring and summer of

1997. Includes all pups born during the calendar

year.

Number of seals

Size Male Female Total

Sex ratio

male:female

Adults 69 45 114 1.5:1

Subadults 19 16 35 1.2:1

Juveniles 7 10 17 0.7:1

Pups 10 12 22 0.8:1

Nonpup Total 95 71 166 1.3:1

Grand Total 105 83 188 1.3:1
47

Table 4.3.--Summary of tagged known-age seals born at Lisianski

Island and resighted there in 1997.

Age

(years) Sex

Number originally

tagged

Number resighted

in 1997

15 Male

Female

7

6

2

2

14 Male

Female

6

18

2

7

13 Male

Female

10

5

4

2

12 Male

Female

5

9

2

2

11 Male

Female

11

9

5

3

10 Male

Female

12

6

1

0

9 Male

Female

10

8

5

5

8 Male

Female

--

--

--

--

7 Male

Female

8

9

4

3

6 Male

Female

9

6

5

2

5 Male

Female

13

8

6

4

4 Male

Female

4

9

2

3

3 Male

Female

4

5

2

2

2 Male

Female

7

10

2

3

1 Male

Female

9

13

3

6
48

Table 4.4 a.--Summary of Hawaiian monk seals born at Lisianski

Island in 1997.

Event

Number of pups

Male Female Total

Born 10 12 22

Died prior to weaning 0 1 1

Still nursing 0 2 2

Weaned 10 9 19

Tagged 10 9 19

Table 4.4b.--Summary of nursing periods and measurements of

weaned pups at Lisianski Island in 1997. Nursing

periods were calculated where both birth and weaning

date ranges were 4 days. All measurements were

taken within 2 weeks after weaning.

Nursing period

(d)

Axillary

girth (cm)

Straight dorsal

length (cm)

Mean 35.1 99.7 121.1

St. Dev. 3.4 8.5 6.2

n 15 19 19
49

Table 4.5a.--Known movement of Hawaiian monk seals to Lisianski

Island from other locations in 1997. Some seals

made more than one trip.

Original location Number, size, and sex class

Laysan Island 3 adult females,

1 subadult female

Pearl and Hermes Reef 1 adult male,

1 subadult male

Table 4.5b.--Known movement of Hawaiian monk seals from Lisianski

Island to other locations in 1997. Some seals made

more than one trip.

Destination Number, size, and sex class

Laysan Island 1 adult male,

6 adult females,

2 subadult females

Pearl and Hermes Reef 1 adult female,

1 subadult male
50

Table 4.6.--Factors affecting Hawaiian monk seal survival at

Lisianski Island in 1997.

Outcome

Size Sex Total Injured Died Probably died

Attack by Large Shark

Adult Male

Female

2

2

2

2

0

0

0

0

Juvenile Male 1 1 0 0

Mounting by Male

Adult Male

Female

1

2a 1

1

0

0

0

0

Entanglement

Juvenile Male 1b 00 0

Weaned pup Female 2c 00 0

Emaciation

Adult Male

Female

2

1

0

0

2d

0

0

1e

Other/Unknown

Adult Female 2 2 0 0

Juvenile Female 1 1 0 0

Nursing pup Female 1 0 1f 0

a

Six males were observed mounting an adult female who sustained

no apparent injuries.

b

Seal released by researchers.

c

Same seal became entangled twice and was released each time

by observers.

d

Poor condition resulted in shark injury and finally, death.

e

Seal not resighted during last 2 months of field season.

f

Neonate, <24 hours old, cause of death undetermined but may have

been crushed by mother or suffocated by the amniotic sac.
CHAPTER 5. THE HAWAIIAN MONK SEAL ON

PEARL AND HERMES REEF, 1997

Chad Yoshinaga, Kim Raum-Suryan, Irene Kinan, Carolyn Cornish

53

Pearl and Hermes Reef (lat. 27°55'N, long. 175°45'W) is one

of the major haulout and pupping locations of the Hawaiian monk

seal. This atoll is located ca. 1,900 km northwest of Oahu in

the Northwestern Hawaiian Islands and is part of the Hawaiian

Islands National Wildlife Refuge (Fig. 1.1). Pearl and Hermes

Reef is composed of four vegetated and three non-vegetated sand

islands enclosed in a fringing reef (Fig. 5.1).

RESEARCH

The National Marine Fisheries Service (NMFS) began research

on Hawaiian monk seals at Pearl and Hermes Reef in 1982. In

1997, research was conducted by NMFS during May 29-July 22 and

October 24-November 3. The perimeters of the four larger

vegetated islands were divided into sectors using natural

landmarks. The smaller sand islands were counted as a single

sector. Research objectives specific to this population in 1997

included (1) investigation of habitat use patterns using

satellite-linked telemetry, and (2) debris removal from the

fringing reef. In addition, seabird counts were conducted on all

islands for the U.S. Fish and Wildlife Service, and recording and

banding of Laysan finches were done on Southeast and North

Islands for Dr. Sheila Conant.

Censuses and Patrols

Atoll censuses (n = 9) were conducted approximately every

3 days, on average, from June 14 to July 20, beginning at 1030

Hawaii standard time and continuing for approximately 5 hours.

All islands were censused on foot by one or two persons. In

addition, incidental patrols were conducted opportunistically to

resight seals tagged in previous years, bleach untagged seals,

and record scars that could be used to identify untagged seals.

Individual Identification

A total of 246 individuals (219 excluding pups) were

identified by existing or applied tags, bleach marks, scars, or

natural markings. All weaned pups (n = 27) were tagged with

Temple Tags; 22 of these same pups were tagged with passive

integrated transponder (PIT) tags. Two of these pups were tagged

in October, and three others were tagged in February 1998. Ten

seals (three adult males, six adult females, and one juvenile

female) were also tagged with Temple Tags. In addition, seven

adult seals were retagged with Temple Tags.

Collection of Samples

Sixty-six scat and spew samples were collected. Tissue

samples were collected from 19 seals during tagging. One skull

sample was collected. In total, 346 pieces of potentially

entangling debris were inventoried and destroyed.
54

Special Studies

Habitat Use Study

In October, 24 seals (9 adult males, 9 adult females, and 6

juvenile males) were instrumented with satellite-linked timedepth recorders as part of a foraging ecology study conducted in

collaboration with the U.S. Fish and Wildlife Service and Hubbs

Sea World Research Institute. Blood samples and measurements

(axillary girth and dorsal straight length) were collected from

all seals during instrumentation.

Debris Removal from Fringing Reef

In October, personnel aboard the NOAA ship Townsend

Cromwell removed debris from a section of fringing reef to reduce

hazards to monk seals and other marine life, assess the extent of

reef fouling, and determine the feasibilility of a large scale

debris removal effort.

RESULTS

Population Abundance and Composition

The means (±SD) for nine atoll censuses were 91.6 seals

(±12.4) including pups, and 77.1 seals (±10.8) excluding pups

(Table 5.1). The total spring-summer population was 240

individuals, 213 excluding pups (Table 5.2). The sex ratios of

nonpup immature seals and adults were 0.8:1 (31 males:39 females)

and 1.2:1 (72 males:60 females), respectively. The numbers of

tagged known-age seals born at Pearl and Hermes Reef during the

period from 1983 to 1996 and resighted there in 1997 are

summarized in Table 5.3.

Reproduction

At least 27 pups were born, and all 27 were weaned

(Table 5.4a). Measurements of weaned pups are summarized in

Table 5.4b. Twenty-seven of sixty (45%) adult-sized females were

parturient.

Interatoll Movement

Interatoll movement was documented for 20 seals that made a

total of 24 movements between Pearl and Hermes Reef and either

Kure Atoll, Midway Atoll, or Lisianski Island (Tables 5.5a and

b).

Factors Affecting Survival
55

Entanglements resulted in two life-threatening conditions

(Table 5.6). Both incidents involved weaned pups entangled in

marine debris. The pups were disentangled and no deaths were

observed during the season. In addition to the incidents

presented in Table 5.6, a mummified skeleton of a juvenile seal

was found buried on Seal Kittery.

ACKNOWLEDGMENTS

We thank the captain, officers, and crew of the NOAA ship

Townsend Cromwell for their logistical support. We also

acknowledge the support of the U.S. Fish and Wildlife Service,

Hawaiian Islands National Wildlife Refuge staff.
TABLES
59

Table 5.1.--Summary statistics for atoll censuses ( n = 9) of

Hawaiian monk seals at Pearl and Hermes Reef from

June 14 to July 20, 1997.

Size/Sex

Mean number of

individuals

Standard

deviation

Adults 50.8 7.5

Male 21.0 4.9

Female 19.7 5.4

Unknown 10.1 2.6

Subadults 17.6 3.6

Male 6.4 2.0

Female 9.4 1.9

Unknown 1.7 1.8

Juveniles 8.7 4.1

Male 4.8 2.0

Female 3.0 1.6

Unknown 0.9 1.2

Pups 14.4 4.2

Male 7.0 2.2

Female 5.2 1.8

Unknown 2.2 1.9

Nonpup Total 77.1 10.8

Grand Total 91.6 12.4
60

Table 5.2.--Composition of the Hawaiian monk seal population at

Pearl and Hermes Reef during the spring and summer of

1997. Includes all pups born during the calendar

year.

Number of seals

Size Male Female Unknown Total

Sex ratio

male:female

Adults 72 60 10 142 1.2:1

Subadults 15 23 0 38 0.7:1

Juveniles 16 16 1 33 1.0:1

Pups 16 11 0 27 1.5:1

Nonpup Total 103 99 11 213 1.0:1

Grand Total 119 110 11 240 1.1:1
61

Table 5.3.--Summary of tagged known-age seals born at Pearl and

Hermes Reef and resighted there in 1997.

Age

(years) Sex

Number originally

tagged

Number resighted

in 1997

14 Male

Female

8

2

4

1

13 Male

Female

5

8

1

2

12 Male

Female

9

6

1

3

11 Male

Female

Unknown

10

7

1

1

2

0

10 Male

Female

14

7

7

2

9 Male

Female

12

6

9

2

8 Male

Female

8

6

5

2

7 Male

Female

5

1

2

0

6 Male

Female

10

11

7

2

5 Male

Female

13

10

7

6

4 Male

Female

14

7

5

4

3 Male

Female

--

--

--

--

2 Male

Female

16

11

9

5

1 Male

Female

11

12

5

7
62

Table 5.4a.--Summary of Hawaiian monk seals born at Pearl and

Hermes Reef in 1997.

Event

Number of pups

Male Female Total

Born 16 11 27

Died prior to weaning 0 0 0

Weaned 16 11 27

Tagged 16 11 27a

a Two male pups were tagged in October, and three pups (2 male,

1 female) were tagged as yearlings in February 1998.

Table 5.4b.--Summary of nursing periods and measurements of

weaned pups at Pearl and Hermes Reef in 1997. All

measurements were taken within 2 weeks after

weaning.

Axillary girth (cm)

Straight dorsal

length (cm)

Mean 106.5 124.9

St. Dev. 6.2 4.4

n 6 6
63

Table 5.5a.--Known movement of Hawaiian monk seals to Pearl and

Hermes Reef from other locations in 1997, summarized

by movements between two locations. Some seals made

more than one trip.

Original location Number, size, and sex class

Lisianski Island 1 adult female,

1 subadult male

Midway Atoll 1 adult male,

4 adult females

Table 5.5b.--Known movement of Hawaiian monk seals from Pearl and

Hermes Reef to other locations in 1997, summarized

by movements between two locations. Some seals made

more than one trip.

Destination Number, size, and sex class

Lisianski Island 1 adult male,

1 subadult male

Midway Atoll 2 adult males,

9 adult females,

2 subadult males

Kure Atoll 1 adult female,

1 subadult male
64

Table 5.6.--Factors affecting Hawaiian monk seal survival at

Pearl and Hermes Reef in 1997.

Outcome

Size Sex Total Injured Died Probably died

Attack by Large Shark

(none observed)

Mounting by Males

(none observed)

Entanglement

Weaned pup Male 1a 00 0

Weaned pup Female 1a 00 0

a

Seal released by observers.
CHAPTER 6. THE HAWAIIAN MONK SEAL ON

MIDWAY ATOLL, 1997

Lucy W. Keith, Heather R. Smith, Heidi J. Auman,

Suzanne Canja, and Cynthia A. Vanderlip

67

Midway Atoll (lat. 28°15'N, long. 177°35'W) has

historically been one of the major haulout and pupping locations

of the endangered Hawaiian monk seal, although current population

levels and pup production are low. This atoll is located 2,100

km northwest of Oahu in the Northwestern Hawaiian Islands (Fig.

1.1) and comprises a circular fringing reef approximately 9 km in

diameter, enclosing a lagoon and three permanent islands (Sand,

Spit, and Eastern Islands) inside the southern part of the reef

(Fig. 6.1). Eastern and Spit Islands are uninhabited. Sand

Island was the site of a U.S. Naval Air Facility until 1993 when

the facility was closed. On June 30, 1997, the Navy transferred

primary management authority to the U.S. Fish and Wildlife

Service (USFWS), which has maintained a refuge (Midway Atoll

National Wildlife Refuge) at the site since 1988.

Beach counts of the Hawaiian monk seal at Midway Atoll

averaged 56 animals in the late 1950s (Kenyon, 1972) but declined

severely by the late 1960s; a single seal was observed during an

aerial survey in 1968 (Kenyon, 1972). From the late 1960s to the

late 1980s the population failed to recover, but recent

assessments suggest that recovery may be beginning because of an

influx of immigrants from Kure Atoll and Pearl and Hermes Reef

and an increasing number of seals born on Midway Atoll. The

earlier counts indicate that the Midway population has

significant potential for growth, and recovery of this population

is an important management goal.

RESEARCH

The National Marine Fisheries Service (NMFS) began limited

population monitoring of Hawaiian monk seals at Midway Atoll in

1983. In 1997, research was conducted by NMFS during April 28-

October 17. Collaborating researchers from the Oceanic Society

and Hawaii Wildlife Fund began data collection on February 20 and

continued through the rest of the year. Incidental observations

were also recorded by USFWS personnel. The perimeters of the

three permanent islands were divided into sectors using

artificial or natural landmarks. In 1997, research objectives

specific to Midway Island included the identification of all

seals in the resident population, tagging pups and other untagged

seals, and radio telemetry tracking of all resident juvenile

seals.

Censuses and Patrols

Atoll censuses (n = 28) were conducted every 7 days, on

average, from June 5 to December 14. All islands were censused

on foot by one or two persons. Each atoll census began between

0830 and 1400 Hawaii standard time and ended between 1454 and

1918. Beach counts of Sand Island (n = 40), Eastern Island

(n = 38), or Spit Island (n = 29) were conducted on non-atoll

census days to identify and resight seals.
68

Individual Identification

A total of 65 individuals (52 excluding pups) were

identified by existing or applied tags, bleach marks, scars, or

natural markings. Most weaned pups (n = 9) were tagged with

Temple Tags and passive integrated transponder (PIT) tags. One

juvenile seal (female) was also tagged with Temple Tags and a PIT

tag. In addition, Temple Tags with radio transmitters epoxied to

their dorsal sides were applied to 9 weaned pups and 3 juvenile

seals.

Collection of Samples

Eighty-two scat samples and three spew samples were

collected. Tissue samples were collected from eight weaned pups

and two juvenile seals during tagging. Necropsy samples were

collected from two seals that were found dead (one female pup and

one subadult male). In total, 540 pieces of potentially

entangling debris were inventoried and destroyed.

Special Studies

Radio Telemetry of Immature Seals

Radio transmitters were applied to 12 seals (9 weaned pups

and 3 juveniles) between May 15 and September 14. Four seals

were recaptured and a second transmitter was applied after the

first one was lost. Five automatically recording receiver

stations were set up to cover all possible haulout locations on

the three islands within the atoll. The results of this study

will be discussed elsewhere.

RESULTS

Population Abundance and Composition

The means (+SD) for 28 atoll censuses were 16.0 seals

(+5.3) including pups and 12.2 seals ( +4.1) excluding pups (Table

6.1). The total spring-summer population was 50 seals, 39

excluding pups (Table 6.2).

The estimation of population abundance is confounded by

movement of seals among Midway Atoll, Kure Atoll, and Pearl and

Hermes Reef. Because of this, it is difficult to distinguish

transient visitors from resident seals. Further study of this

population is needed to identify resident seals and thereby

provide a more reliable measure of abundance at Midway.

The numbers of tagged known-age seals born at Midway Atoll

during the period from 1988 to 1996 and resighted there in 1997

are summarized in Table 6.3.

Reproduction
69

At least 11 pups were born: 10 were weaned and 1 died

prior to weaning (Table 6.4a). One pup was born on the closed

beach on Sand Island; this pup weaned successfully and is the

first recorded birth on Sand, the largest and only populated

island at Midway Atoll. Measurements of weaned pups are

summarized in Table 6.4b. Eleven of twenty (55%) adult-sized

females were parturient.

Interatoll Movement

Interatoll movement was documented for 32 seals that made a

total of 40 movements between Midway Atoll and either Pearl and

Hermes Reef or Kure Atoll (Tables 6.5a and b). Interatoll

movement of weaned pups was detected for the first time; 2 pups

(1 male and 1 female) moved from Kure Atoll to Midway Atoll in

August 1997.

Factors Affecting Survival

Attacks by large sharks, entanglements, and unknown factors

led to five life-threatening conditions, which resulted in the

confirmed deaths of two animals (Table 6.6). One entanglement

was documented; a female weaned pup was found entangled and was

released by observers.

ACKNOWLEDGMENTS

We acknowledge the support of the U.S. Fish and Wildlife

Service, Midway Atoll National Wildlife Refuge. Special thanks

are extended to Nanette Seto, Robert Shallenberger, Bob Dieli,

Bart McDermott, James Aliberti, and Jim Nestler for assistance

with radio telemetry research; and to Kenneth Niethammer, Jon

Hale, Pat Whitebear, and R. Sudarshan for logistical assistance.

We also thank the officers and crew of the NOAA ship Townsend

Cromwell for logistical assistance.
TABLES
73

Table 6.1.--Summary statistics for atoll censuses ( n = 28) of

Hawaiian monk seals at Midway Atoll from June 5 to

December 14, 1997.

Size/Sex

Mean number of

individuals

Standard

deviation

Adults 9.1 2.9

Male 3.0 1.5

Female 5.3 2.7

Unknown 0.8 1.0

Subadults 2.2 1.8

Male 1.0 0.9

Female 0.9 1.0

Unknown 0.3 0.5

Juveniles 0.8 0.9

Male 0.1 0.3

Female 0.7 0.8

Unknown 0.1 0.3

Pups 3.9 2.3

Male 1.0 1.0

Female 2.6 1.6

Unknown 0.3 0.5

Nonpup Total 12.2 4.1

Grand Total 16.0 5.3
74

Table 6.2.--Composition of the Hawaiian monk seal population at

Midway Atoll during the spring and summer of 1997;

includes all pups born during the calendar year.

Number of seals

Size Male Female Unknown Total

Sex ratio

male:female

Adults 10 20 0 30 0.5:1

Subadults 2 4 0 6 0.5:1

Juveniles 1 2 0 3 0.5:1

Pups 3 7 1 11 0.4:1

Nonpup Total 13 26 0 39 0.5:1

Grand Total 16 33 1 50 0.5:1
75

Table 6.3.--Summary of tagged known-age seals born at Midway

Atoll and resighted there in 1997.

Age

(years) Sex

Number originally

tagged

Number resighted

in 1997

9 Male

Female

0

1

--

1

8 Male

Female

0

0

--

--

7 Male

Female

0

0

--

--

6 Male

Female

1

1

1

1

5 Male

Female

0

1

--

1

4 Male

Female

1

0

0

--

3 Male

Female

0

0

--

--

2 Male

Female

Unknown

1

6

1

1

1

0

1 Male

Female

1

4

0

1
76

Table 6.4a.--Summary of Hawaiian monk seals born at Midway

Atoll in 1997.

Event

Number of pups

Male Female Unknown Total

Born 3 7 1 11

Died prior to weaning 0 1 0 1

Weaned 3 6 1 10

Tagged 3 6 0 9

Table 6.4b.--Summary of nursing periods and measurements of

weaned pups at Midway Atoll in 1997. All

measurements were taken within 2 weeks after

weaning.

Nursing period

(d)

Axillary

girth (cm)

Straight dorsal

length (cm)

Mean 39.5 110.2 131.0

St. Dev. 4.4 3.8 2.7

n 34 4
77

Table 6.5a.--Known movement of Hawaiian monk seals to Midway

Atoll from other locations in 1997, summarized by

movements between two locations. Some seals made

more than one trip.

Original location Number, size, and sex class

Pearl and Hermes Reef 2 adult males,

9 adult females,

2 subadult males

Kure Atoll 4 adult males,

6 adult females,

2 subadult male,

1 subadult female,

2 juvenile males,

1 weaned pup male,

1 weaned pup female

Table 6.5b.--Known movement of Hawaiian monk seals from Midway

Atoll to other locations in 1997, summarized by

movements between two locations. Some seals made

more than one trip.

Destination Number, size, and sex class

Pearl and Hermes Reef 1 adult male,

4 adult females

Kure Atoll 1 adult male,

2 adult females,

1 juvenile male,

1 juvenile female
78

Table 6.6.--Factors affecting Hawaiian monk seal survival at

Midway Atoll in 1997.

Outcome

Size Sex Total Injured Died Probably died

Attack by Large Shark

Adult Female 2 2 0 0

Mounting by Males

(none observed)

Entanglement

Weaned pup Female 1a 00 0

Unknown

Juvenile Male 1 0 1 0

Nursing pup Female 1 0 1 0

a

Seal released by observers.
CHAPTER 7. THE HAWAIIAN MONK SEAL ON

KURE ATOLL, 1997

Katherine W. McFadden and Bradley C. Ryon
880
81

Kure Atoll (lat. 28°25'N, long. 178°10'W) is one of the

major haulout and pupping locations of the Hawaiian monk seal.

The atoll is located ca. 2,300 km northwest of Oahu in the

Northwestern Hawaiian Islands (Fig. 1.1) and is a seabird

sanctuary of the State of Hawaii. The atoll consists of a

circular fringing reef approximately 9 km in diameter, the

enclosed lagoon, one permanent vegetated island (Green Island),

two sand islets (Sand and Shark Islets), and a sometimes emergent

area known locally as Stark Reef (Fig. 7.1). Until 1992, Green

Island was the site of a U.S. Coast Guard (USCG) LORAN station,

commissioned in 1961 and staffed by 20-30 USCG personnel. In

July 1992, this station was closed and vacated by the USCG,

leaving the atoll uninhabited. In 1993, the USCG completed the

removal of buildings and other structures on Green Island.

The Kure Atoll population of Hawaiian monk seals has been

growing in recent years due, in part, to a reduction of human

disturbance and to two capture-and-release programs designed to

increase recruitment of females. The Head Start Project (1981-

91) involved the capture and protection of weaned female pups

from Kure Atoll during the transition phase from weaning to

independent feeding. The Rehabilitation Project (1984-91 and

1993-95) involved the capture of undersized weaned female pups

from French Frigate Shoals, conditioning on Oahu, and then

transport to Kure Atoll for release. Continued monitoring of

seals involved in these projects is considered imperative to

evaluate the projects' long-term success.

RESEARCH

The National Marine Fisheries Service (NMFS) began research

on Hawaiian monk seals at Kure Atoll in 1981. In 1997, research

was conducted by NMFS during May 30-July 20. The perimeter of

Green Island was divided into eight sectors, using artificial or

natural landmarks. Research objectives for the Kure Atoll monk

seal population in 1997 included the identification of all seals,

evaluation of the success of past seal introductions, and the use

of photogrammetry as a means to assess body size.

Censuses and Patrols

Atoll censuses (n = 9) were conducted approximately every

3-4 days, weather permitting, from June 16 to July 19. Each

census began at approximately 1300 Hawaii standard time and ended

between 1517 and 1632. All islands were censused on foot by one

or two persons. Stark Reef was not emergent during the 1997

field season. Patrols were conducted to identify seals and

monitor locations used by parturient females.
82

Individual Identification

A total of 114 individuals (96 excluding pups) were

identified by existing or applied tags, bleach marks, scars, or

natural markings. Most weaned pups (n = 16) were tagged with

Temple Tags and passive integrated transponder (PIT) tags. One

juvenile seal (female) was also tagged with Temple Tags.

Collection of Samples

Twenty-nine scat and spew samples were collected. Tissue

samples were collected from 11 weaned pups and 1 other seal

during tagging. In total, 320 pieces of potentially entangling

debris were inventoried; 2 entanglement items were removed from

seals and collected. The remainder was destroyed before the end

of the field season.

Special Studies

Assessment of Photogrammetry as a Tool to Estimate Body Size

During the 1997 field season, weaned pups were

photographed, measured, and weighed in order to assess whether

photographs could be used as a noninvasive means to assess size

and condition. A rigid measuring pole was positioned over the

seals while sleeping and photographs of two views (either

anterior/posterior or viewed from the side) were taken at various

camera heights and distances. The goal of this project was to

determine if a predictive relationship could be established

between photographically measured variables (digitized side,

anterior/posterior area, length, width), which may aid

researchers in more accurately predicting size and condition.

RESULTS

Population Abundance and Composition

The means (±SD) for nine atoll censuses were 50.1 seals

(+7.9) including pups and 42.7 seals ( +6.3) excluding pups (Table

7.1). The total spring-summer population was 112 individuals, 94

seals excluding pups (Table 7.2). The numbers of tagged knownage seals born at Kure Atoll during the period from 1981 to 1996

and resighted there in 1997 are summarized in Table 7.3.

Reproduction

At least 18 pups were born: 17 were weaned and 1 died

prior to weaning (Table 7.4a). Nursing periods and measurements

of weaned pups are summarized in Table 7.4b. Of the 39 adultsized females identified, a minimum of 18 were parturient (46%).

At least 3 of these 18 parturient females had been temporarily

maintained as pups in the Kure Atoll Head Start enclosure (2 in
83

1985 and 1 in 1984), and none were rehabilitated seals from FFS

introduced to Kure as yearlings.

Interatoll Movement

Interatoll movement was documented for 20 seals that made a

total of 24 movements between Kure Atoll and either Midway Atoll

or Pearl and Hermes Reef (Table 7.5a and b).

Factors Affecting Survival

Mounting attempts by male seals, entanglement in debris,

and unknown factors resulted in four life-threatening conditions,

which led to the death of one seal (Table 7.6). In the mounting

incident, two seals were seen repeatedly attempting to mount a

weaned pup. The same pup was later resighted with no visible

injuries. Two entanglements were documented; in both incidents

the weaned pup was released by observers. One pup was found dead

by Department of Forestry and Wildlife researchers prior to the

NMFS 1997 field season.

ACKNOWLEDGMENTS

We acknowledge the support of the State of Hawaii,

Department of Land and Natural Resources, Division of Forestry

and Wildlife, and the Coast Guard ship Kiska. We thank the

captains and crew of the NOAA ship Townsend Cromwell for

logistical support and for transport to and from Kure Atoll.
TABLES
87

Table 7.1.--Summary statistics for atoll censuses ( n = 9) of

Hawaiian monk seals at Kure Atoll from June 16 to

July 19, 1997.

Size/Sex

Mean number of

individuals

Standard

deviation

Adults 26.0 4.0

Male 8.2 1.9

Female 17.3 3.9

Unknown 0.4 0.7

Subadults 10.0 2.5

Male 6.2 1.4

Female 3.6 1.4

Unknown 0.2 0.4

Juveniles 6.7 1.6

Male 5.0 1.6

Female 1.6 0.5

Unknown 0.1 0.3

Pups 7.4 3.1

Male 4.6 2.3

Female 2.8 0.8

Unknown 0.1 0.3

Nonpup Total 42.7 6.3

Grand Total 50.1 7.9
88

Table 7.2.--Composition of the Hawaiian monk seal population at

Kure Atoll during the spring and summer of 1997.

Includes all pups born during the calendar year.

Number of seals

Size Male Female Unknown Total

Sex ratio

male:female

Adults 23 39 0 62 0.6:1

Subadults 12 8 0 20 1.5:1

Juveniles 9 3 0 12 3.0:1

Pups 10 7 1 18 1.4:1

Nonpup Total 44 50 0 94 0.9:1

Grand Total 54 57 1 112 0.9:1
89

Table 7.3.--Summary of tagged known-age seals born at Kure Atoll

and resighted there in 1997.

Age

(years) Sex

Number originally

tagged

Number resighted

in 1997

16 Male

Female

3

5

2

1

15 Male

Female

1

3

0

2

14 Male

Female

4

0

2

--

13 Male

Female

4

2

1

2

12 Male

Female

2

3

1

3

11 Male

Female

1

0

0

--

10 Male

Female

1

3

1

2

9 Male

Female

2

5

2

2

8 Male

Female

5

4

2

1

7 Male

Female

3

3

0

2

6 Male

Female

7

6

4

2

5 Male

Female

5

8

3

5

4 Male

Female

9

4

5

2

3 Male

Female

3

0

0

--

2 Male

Female

6

5

4

3

1 Male

Female

10

6

7

2
90

Table 7.4a.--Summary of Hawaiian monk seals born at Kure Atoll in

1997.

Event

Number of pups

Male Female Unknown Total

Born 10 7 1 18

Died prior to weaning 0 0 1 1

Weaned 10 7 0 17

Tagged 9a 7a 0 16

a

Three pups born in 1997 (one male and two females) were tagged

in 1998.

Table 7.4b.--Summary of nursing periods and measurements of

weaned pups at Kure Atoll in 1997. Nursing periods

were calculated where both birth and weaning date

ranges were 4 days. All measurements were taken

within 2 weeks after weaning.

Nursing

period (d)

Axillary

girth (cm)

Straight

dorsal length

(cm)

Net

Weight

(kg)

Mean 32.5 111.5 130.0 66.4

St. Dev. -- 1.9 1.4 6.8

n 1 4 44
91

Table 7.5a.--Known movement of Hawaiian monk seals to Kure Atoll

from other locations in 1997, summarized by

movements between two locations. Some seals made

more than one trip.

Original location Number, size, and sex class

Pearl and Hermes Reef 1 adult female,

1 subadult male

Midway Atoll 1 adult male,

2 adult females,

1 juvenile male,

1 juvenile female

Table 7.5b.--Known movement of Hawaiian monk seals from Kure

Atoll to other locations in 1997, summarized by

movements between two locations. Some seals made

more than one trip.

Destination Number, size, and sex class

Midway Atoll 4 adult males,

6 adult females,

2 subadult males,

1 subadult female,

2 juvenile males,

1 weaned pup male,

1 weaned pup female
92

Table 7.6.--Factors affecting Hawaiian monk seal survival at Kure

Atoll in 1997.

Outcome

Size Sex Total Injured Died Probably died

Attack by Large Shark

(none observed)

Mounting by Males

Weaned pup Female 1a 00 0

Entanglement

Weaned pup Male 2b 00 0

Unknown

Nursing pup Unknown 1c 01 0

a

Two males observed attempting to mount a weaned pup.

b

Seals released by observers.

c

Dead pup discovered by State researchers prior to NMFS field

season.
CHAPTER 8. THE HAWAIIAN MONK SEAL ON

NECKER ISLAND, 1997

Chad Yoshinaga and Kim Raum-Suryan

95

Necker Island (lat. 23°36'N, long. 164°42'W) (Fig. 8.1) is

located ca. 750 km northwest of Oahu in the Northwestern Hawaiian

Islands (Fig. 1.1). This island lies within the Hawaiian Islands

National Wildlife Refuge. Although endangered Hawaiian monk

seals use this island, pup production is limited by lack of

haulout area.

RESEARCH

Research was conducted by the National Marine Fisheries

Service on July 27, 1997. The perimeter of the island was

divided into 10 sectors using natural landmarks. Beginning in

1989, the monk seal population at French Frigate Shoals began to

decline, largely from loss of juvenile seals. In 1997, research

objectives specific to the Necker Island monk seal population

included the assessment of the extent of monk seal migration from

French Frigate Shoals to this location to determine if migration

may have contributed to the decline observed at French Frigate

Shoals.

Censuses and Patrols

One census was conducted beginning at 0800 Hawaii standard

time and continuing for approximately 6 hours. The island was

censused both on foot and by boat.

Individual Identification

One molting adult female was identified by tags applied at

French Frigate Shoals.

Collection of Samples

No samples were collected during the census of the island.

RESULTS

Population Abundance and Composition

The census total was 11 seals (10 adults and 1 pup). The

sex ratio of the adults was 1:1 (3 males:3 females) with 4 of

unknown sex. In all, a total of 12 adult seals were observed on

or around the island. Because of limited effort, the composition

of the spring-summer population was not determined.
96

Reproduction

At least one pup was born. The only pup observed was

female, and still nursing. The mother was untagged with no

distinguishing marks or scars.

Interatoll Movement

Interatoll movement was documented for one seal that made a

total of one movement between Necker Island and French Frigate

Shoals (Tables 8.1a and b).

Factors Affecting Survival

No factors affecting survival were observed.

ACKNOWLEDGMENTS

We thank the captain, officers, and crew of the NOAA ship

Townsend Cromwell for their logistical support. We also

acknowledge the support of the U.S. Fish and Wildlife Service,

Hawaiian Islands National Wildlife Refuge staff.
TABLES
99

Table 8.1a.--Known movement of Hawaiian monk seals to Necker

Island from other locations in 1997, summarized by

movements between two locations.

Original location Number, size, and sex class

French Frigate Shoals 1 adult female

Table 8.1b.--Known movement of Hawaiian monk seals from Necker

Island to other locations in 1997, summarized by

movements between two locations.

Destination Number, size, and sex class

(None observed)
REFERENCES
103

Alcorn, D. J.

1984. The Hawaiian monk seal on Laysan Island: 1982. U.S.

Dep. Commer., NOAA Tech. Memo., NOAA-TM-NMFS-SWFC-42, 37

p.

American Society of Mammalogists, Committee on Marine Mammals.

1967. Standard Measurements of Seals. J. Mammal. 48:459-

462.

Boness, D. J.

1990. Fostering behavior in Hawaiian monk seals: is there a

reproductive cost? Behav. Ecol. Sociobiol. 27:113-122.

DeMartini, E. E., F. A. Parrish, and J. D. Parrish.

1993. Temporal changes in reef prey populations at French

Frigate Shoals, NWHI: Implications for juvenile monk seal

(Monachus schauinslandi) predators. Honolulu Lab.,

Southwest Fish. Sci. Cent., Natl. Mar. Fish. Serv., NOAA,

Honolulu, HI 96822-2396, Southwest Fish. Cent. Admin. Rep.

H-93-06, 49 p.

Gilmartin, W. G. and T. Gerrodette.

1986. Hawaiian monk seal status and recovery potential at

Kure Atoll. Honolulu Lab., Southwest Fish. Cent., Natl.

Mar. Fish. Serv., NOAA, Honolulu, HI 96822-2396, Southwest

Fish. Cent. Admin. Rep. H-86-16, 26 p.

Hiruki, L. M., Gilmartin, W. G., Becker, B. L., and Stirling, I.

1993. Wounding in Hawaiian monk seals ( Monachus

schauinslandi). Can. J. Zool. 71:458-468.

Johanos, T. C. and Kam, A. K. H.

1986. The Hawaiian monk seal on Lisianski Island: 1983.

U.S. Dep. Commer., NOAA Tech. Memo., NOAA-TM-NMFS-SWFC-58,

37 p.

Johanos, T. C., A. K. H. Kam, and R. G. Forsyth.

1987. The Hawaiian monk seal on Laysan Island: 1984. U.S.

Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFC-70, 38 p.

Kenyon, K. W.

1972. Man versus the monk seal. J. of Mammal. 53(4):687-

696.

Lombard, K. B., B. L. Becker, M. P. Craig, G. C. Spencer, and K.

Hague-Bechard.

1994. The Hawaiian monk seal on Laysan Island, 1990. U.S.

Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFSC-206, 16

p.

Stone, H. S.

1984. Hawaiian monk seal population research, Lisianski

Island, 1982. U.S. Dep. Commer., NOAA Tech. Memo. NOAATM-NMFS-SWFC-47, 33 p.

Winchell, J.

1990. Field manual for phocid necropsies (specifically

Monachus schauinslandi). U.S. Dep. Commer., NOAA Tech.

Memo. NOAA-TM-NMFS-SWFSC-146, 55 p.
APPENDIXES
107

Appendix A.--Reports summarizing annual field research on the

Hawaiian monk seal by the National Marine Fisheries

Service and collaborating scientists.

All islands

Johanos, T. C., and T. J. Ragen (Eds.).

1999. The Hawaiian monk seal in the Northwestern Hawaiian

Islands, 1996. U.S. Dep. Commer., NOAA Tech. Memo., NOAATM-NMFS-SWFSC-259, 134 p.

Johanos, T. C., and T. J. Ragen (Eds.).

1997. The Hawaiian monk seal in the Northwestern Hawaiian

Islands, 1995. U.S. Dep. Commer., NOAA Tech. Memo., NOAATM-NMFS-SWFSC-241, 121 p.

Johanos, T. C., and T. J. Ragen (Eds.).

1996. The Hawaiian monk seal in the Northwestern Hawaiian

Islands, 1993. U.S. Dep. Commer., NOAA Tech. Memo., NOAATM-NMFS-SWFSC-227, 141 p.

Johanos, T. C., and T. J. Ragen (Eds.).

1996. The Hawaiian monk seal in the Northwestern Hawaiian

Islands, 1994. U.S. Dep. Commer., NOAA Tech. Memo., NOAATM-NMFS-SWFSC-229, 111 p.

Johanos, T. C., L. M. Hiruki, and T. J. Ragen (Eds.).

1995. The Hawaiian monk seal in the Northwestern Hawaiian

Islands, 1992. U.S. Dep. Commer., NOAA Tech. Memo., NOAATM-NMFS-SWFSC-216, 128 p.

French Frigate Shoals

Craig, M. P., J. L. Megyesi, C. S. Hall, J. L. Glueck, L. P.

Laniawe, E. A. Delaney, S. S. Keefer, M. A. McDermond, M.

Schulz, G. L. Nakai, B. L. Becker, L. M. Hiruki, and R. J.

Morrow.

1994. The Hawaiian monk seal at French Frigate Shoals,

1990-91. U.S. Dep. Commer., NOAA Tech. Memo., NOAA-TMNMFS-SWFSC-210, 70 p.

Craig, M. P., D. J. Alcorn, R. G. Forsyth, T. Gerrodette, M. A.

Brown, B. K. Choy, L. Dean, L. M. Dennlinger, L. E. Gill, S. S.

Keefer, M. M. Lee, J. S. Lennox, C. R. Lorence, G. L. Nakai,

and K. R. Niethammer.

1992. The Hawaiian monk seal at French Frigate Shoals,

1988-89. U.S. Dep. Commer., NOAA Tech. Memo. NOAA-TMNMFS-SWFSC-178, 83 p.

Eliason, J. J., J. R. Henderson, and M. A. Webber.

1993. Hawaiian monk seal observations at French Frigate

Shoals, 1985. U.S. Dep. Commer., NOAA Tech. Memo. NOAATM-NMFS-SWFSC-187, 46 p.
108

Eliason, J. J., and J. R. Henderson.

1992. Hawaiian monk seal observations at French Frigate

Shoals, 1984. U.S. Dep. Commer., NOAA Tech. Memo. NOAATM-NMFS-SWFSC-177, 61 p.

Fairaizl, G. W.

1984. Intra-atoll resighting of the Hawaiian monk seal,

Monachus schauinslandi, at French Frigate Shoals, 1

January 1983-31 August 1983. Southwest Fish. Cent.

Honolulu Lab., Natl. Mar. Fish Serv., NOAA, Honolulu, HI

96822-2396. Southwest Fish. Cent. Admin. Rep. H-84-5C,

27 p.

Johnson, P. A., and B. W. Johnson.

1984. Hawaiian monk seal observations on French Frigate

Shoals, 1980. U.S. Dep. Commer., NOAA Tech. Memo. NOAATM-NMFS-SWFC-50, 47 p.

Laysan Island

Alcorn, D.

1984. The Hawaiian monk seal on Laysan Island: 1982. U.S.

Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFC-42, 37 p.

Alcorn, D. J., and E. K. Buelna.

1989. The Hawaiian monk seal on Laysan Island, 1983. U.S.

Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFC-124, 46

p.

Alcorn, D. J., and R. L. Westlake.

1993. The Hawaiian monk seal on Laysan Island, 1986. U.S.

Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFSC-191, 25 p.

Becker, B. L., P. A. Ching, L. M. Hiruki, and S. A. Zur.

1994. The Hawaiian monk seal on Laysan Island, 1987 and

1989. U.S. Dep. Commer., NOAA Tech. Memo. NOAA-TMNMFS-SWFSC-213, 20 p.

Becker, B. L., R. J. Morrow, and J. K. Leialoha.

1989. Censuses and interatoll movements of the Hawaiian

monk seal on Laysan Island, 1985. U.S. Dep. Commer., NOAA

Tech. Memo. NOAA-TM-NMFS-SWFC-135, 25 p.

Becker, B. L., K. E. O'Brien, K. B. Lombard, and L. P. Laniawe.

1995. The Hawaiian monk seal on Laysan Island, 1991. U.S.

Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFSC-214, 16

p.

Johanos, T. C., and S. L. Austin.
109

1988. Hawaiian monk seal population structure,

reproduction, and survival on Laysan Island, 1985. U.S.

Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFC-118, 38

p.

Johanos, T. C., B. L. Becker, M. A. Brown, B. K. Choy, L. M.

Hiruki, R. E. Brainard, and R. L. Westlake

1990. The Hawaiian monk seal on Laysan Island, 1988. U.S.

Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFSC-151, 24

p.

Johanos, T. C., A. K. H. Kam, and R. G. Forsyth.

1987. The Hawaiian monk seal on Laysan Island: 1984. U.S.

Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFC-70, 38 p.

Johnson, B. W., and P. A. Johnson.

1984. Observations of the Hawaiian monk seal on Laysan

Island from 1977 through 1980. U.S. Dep. Commer., NOAA

Tech. Memo. NOAA-TM-NMFS-SWFC-49, 65 p.

Lombard, K. B., B. L. Becker, M. P. Craig, G. C. Spencer, and K.

Hague-Bechard.

1994. The Hawaiian monk seal on Laysan Island, 1990. U.S.

Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFSC-206, 16

p.

Lisianski Island

Alcorn, D. J., R. G. Forsyth, and R. L. Westlake.

1988. Hawaiian monk seal research on Lisianski Island, 1984

and 1985. U.S. Dep. Commer., NOAA Tech. Memo. NOAA-TMNMFS-SWFC-120, 22 p.

Johanos, T. C., and J. R. Henderson.

1986. Hawaiian monk seal reproduction and injuries on

Lisianski Island, l982. U.S. Dep. Commer., NOAA Tech.

Memo. NOAA-TM-NMFS-SWFC-64, 7 p.

Johanos, T. C., and A. K. H. Kam.

1986. The Hawaiian monk seal on Lisianski Island: 1983.

U.S. Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFC-58,

37 p.

Johanos, T. C., and R. P. Withrow.

1988. Hawaiian monk seal and green turtle research on

Lisianski Island, 1987. U.S. Dep. Commer., NOAA Tech.

Memo. NOAA-TM-NMFS-SWFC-121, 18 p.

Lee, M. M., L. K. Timme, R. Van Toorenburg, and B. L. Becker.
110

1993. The Hawaiian monk seal on Lisianski Island, 1988 and

1990. U.S. Dep. Commer., NOAA Tech. Memo. NOAA-TM-NMFSSWFSC-179, 33 p.

Stone, H. S.

1984. Hawaiian monk seal population research, Lisianski

Island, 1982. U.S. Dep. Commer., NOAA Tech. Memo. NOAATM-NMFS-SWFSC-47, 33 p.

Westlake, R. L., and P. J. Siepmann.

1988. Hawaiian monk seal and green turtle research on

Lisianski Island, 1986. U.S. Dep. Commer., NOAA Tech.

Memo. NOAA-TM-NMFS-SWFC-119, 18 p.

Pearl and Hermes Reef

Choy, B. K., and L. M. Hiruki.

1992. The Hawaiian monk seal and green turtle on Pearl and

Hermes Reef, 1988. U.S. Dep. Commer., NOAA Tech. Memo.

NOAA-TM-NMFS-SWFSC-175, 18 p.

Finn, M. A., J. R. Henderson, B. L. Becker, and T. J. Ragen.

1993. The Hawaiian monk seal and green turtle at Pearl and

Hermes Reef, 1990 and 1992. U.S. Dep. Commer., NOAA Tech.

Memo. NOAA-TM-NMFS-SWFSC-182, 29 p.

Forsyth, R. G., D. J. Alcorn, T. Gerrodette, and W. G. Gilmartin.

1988. The Hawaiian monk seal and green turtle on Pearl and

Hermes Reef, 1986. U.S. Dep. Commer., NOAA Tech. Memo.

NOAA-TM-NMFS-SWFC-107, 24 p.

Kure Atoll

Bowlby, C. E., P. Scoggins, R. Watson, and M. Reddy.

1991. The Hawaiian monk seal, Monachus schauinslandi, at

Kure Atoll, 1982-83. U.S. Dep. Commer., NOAA Tech. Memo.

NOAA-TM-NMFS-SWFSC-155, 28 p.

Gilmartin, W. G., R. J. Morrow, and A. M. Houtman.

1986. Hawaiian monk seal observations and captive

maintenance project at Kure Atoll, l981. U.S. Dep.

Commer., NOAA Tech. Memo. NOAA-TM-NMFS-SWFC-59, 9 p.

Henderson, J. R., and M. R. Finnegan

1990. Population monitoring of the Hawaiian monk seal,

Monachus schauinslandi, and captive maintenance project at

Kure Atoll, 1988. U.S. Dep. Commer., NOAA Tech. Memo.

NOAA-TM-NMFS-SWFSC-150, 24 p.

Reddy, M. L.

1989. Population monitoring of the Hawaiian monk seal,

Monachus schauinslandi, and captive maintenance project
111

for female pups at Kure Atoll, 1987. U.S. Dep. Commer.,

NOAA Tech. Memo. NOAA-TM-NMFS-SWFC-123, 37 p.

Reddy, M. L., and C. A. Griffith.

1988. Hawaiian monk seal population monitoring, pup captive

maintenance program, and incidental observations of the

green turtle at Kure Atoll, 1985. U.S. Dep. Commer., NOAA

Tech. Memo. NOAA-TM-NMFS-SWFC-101, 35 p.

Van Toorenburg, R. A., W. G. Gilmartin, and J. R. Henderson.

1993. Composition of the Hawaiian monk seal population at

Kure Atoll, 1990. Pac. Sci. 47(3):211-214.

Nihoa and Necker Islands

Conant, S.

1985. Observations of Hawaiian monk seals on Necker

Island, Northwestern Hawaiian Islands. 'Elepaio. 6(2):11-

12.

Finn, M. A. and M. A. Rice.

1994. Hawaiian monk seal observations at Necker Island,

1993. 'Elepaio. 55(9):55-58.

Morrow, R. J., and E. K. Buelna.

1985. The Hawaiian monk seal and green turtle on Necker

Island, 1983. U.S. Dep. Commer., NOAA Tech. Memo. NOAATM-NMFS-SWFC-55, 11 p.
113

Appendix B.--Hawaiian monk seal census form and 1997 census form

directions.

(See following pages.)


117

1997

CENSUS FORM DIRECTIONS

(Unabridged - Laysan and Lisianski Islands only)

This form is used to record all Hawaiian monk seal and green turtle

sightings. Turtle sightings are recorded only during census activities (not

during patrols).

All original data should be coded in pencil. Never erase data once you

have left the recording site. Instead, cross errors out with a single line.

Field editing is editing before running the data entry and checking program.

All field editing by the data collector should be in blue, and field editing

by others should be in red. As soon as you begin the entry and checking

program, the computer will assign the computer page number and display it on

the screen. At this point, be sure to fill it in on your census form. All

editing after this point should be in orange. After completing the entry and

checking program, check off and initial the ENTERED box on the census form.

A separate data sheet should be filled out for each date, observer, data

type, and island within an atoll. If no seals are present, you should still

fill out the information at the top of the census form and write "No seals" in

the data area (only enter the header information). If the island itself is

not present, indicate this by using 99 for the sector code, leaving the rest

of the (first) line blank. To save paper, you should use a census form with

multiple headers if you only have a few seals to record (i.e., at some islands

within an atoll, or when recording incidental sightings before or after census

or patrol). In essence, on a census form with multiple headers, each header

and its associated lines represents a separate data sheet.

If two people conduct the census, they should have the same weather and

the same begin and end time (i.e., both begin at the same time and place and

proceed in opposite directions until they meet on the other side of the island

or islet) and combine pages into one set. Patrols may be conducted by more

than one observer, but page sets are not combined, and header information may

differ. Patrol observers should attempt to start at roughly the same time.

The sum of all observers' patrol activity for a day should result in one

complete island count.

Always record disturbance. You must be honest about this! Fill out a

census form to document disturbance if you disturb a seal when you are not

otherwise collecting data. On a census or atoll count, it is also assumed

that condition and molt data will be taken.

Do not make up additional codes. If the need for an additional code

arises, contact Honolulu.

PAGE HEADER

DATA TYPE

C = Census: A complete, timed count on an island begun around

1300. Census is conducted as quickly as possible (while

gathering all information).

A = Atoll-wide census (must be completed within 2 days).

B = Behavior patrol: A complete, untimed count where size, sex,

ID, and disturbance are recorded. Associations are coded if
118

they involve adult or subadult seals (Laysan and Lisianski

Islands only in 1997).

P = Patrol: A complete, untimed count where size, sex, ID, and

disturbance are recorded. Behavior data is not taken.

I = Incidental observation.

T = Tag status entry for non-active tags (tags not currently on

a seal). Record tag status (F or R) in notes columns.

COMPUTER PAGE NO. Leave this blank during data collection. It will be

assigned and displayed on the screen when you enter the

data. At that time, be sure to fill in the computer page

number on your census form, as this number is needed for

data retrieval.

PAGE Page number within a census or patrol. For example, if the census

(or patrol) requires three pages, then mark the first page as "page 1

of 3" and so on. If more than one person conducts the census, then

combine page numbers; person A has pages 1 and 2, while person B has

pages 3 and 4 of a four-page census day.

ISLAND Name of island and atoll, e.g., East, FFS.

OBSERVER Three initials. If no middle initial, use the first and last

block.

TIME BEGIN and END On a 24-hour clock, e.g., 6 p.m. = 1800, for the group

of pages.

DATE The date that data are collected (in YYMMDD format).

NUMBER Censuses, Atoll counts, Behavior patrols, and Patrols must be

numbered. Each data type will have its own three-digit number

series, starting with 001.

Weather information (except temperature) should be a summary of the entire day

up until the end of the census or patrol, not merely an instantaneous

observation.

TEMP. Temperature in degrees Celsius at beginning of census or patrol.

WIND Speed: 0 = no wind, calm (<5 knots)

1 = light breeze (5-15 knots)

2 = strong wind (>15 knots)

Direction: NN,NE,EE,SE,SS,SW,WW,NW

Thus, 2 N N = strong wind from north

CLOUD Cloud cover: 00 = no clouds

01-09 = 10 to 90% cover

10 = 100% cover

PREC. Precipitation: 0 = no precipitation or trace

1 = mist/drizzle

2 = rain

3 = intermittent rain

LINES

CONTINUE If the same seal sighting is recorded on several lines for any

reason (e.g., additional tag or association, behavior at a later

time, change of beach position), put the original line number you

are continuing from here. Lines may be continued only within the

same page. All fields from SECTOR through MOLT will be copied
119

from the original line if left blank on the continuation line.

Several lines can have the same continuation line number.

Make a new original line (i.e., do not use continuation lines) for

a seal each time that you come abreast of it on census or patrol.

TIME The time should be recorded for each seal sighting, on a 24-hour

clock.

SECTOR Location on island (e.g., 1-20 on Laysan)

Special codes as follows:

00 = unknown sector

77 = pen

88 = offshore spit

99 = island not present

SIZE Size is estimated using a classification scheme from Stone (1984), using

the following terminology:

Pup Seals born within the calendar year. Newborn pups are black

and weigh ca. 11 to 15 kg. Pups molt to a silver-gray

pelage near weaning. Weaning weight is ca. 50 to 80 kg.

Juvenile Short, slight seals from the length of a weaned pup (about

138 cm) to 20-30 cm longer includes yearlings and other

young seals up to 3 years. Distinguished from pups by

thinness and pelage color.

Subadults Seals perceptibly longer than juveniles up to breeding size;

less robust than adults, generally with lighter pelage.

Immature seals ca. 3 to 5 or 6 years old.

Adult Reproductively active or breeding size seals at least as

long as known breeders. Mature or probably mature seals.

Adult females often have extensive back scars or wounds;

adult males usually dark, including venter, and extensively

scarred.

Code size as follows:

Nursing pups

P = Nursing pup

P1 = Nursing pup, wrinkles

P2 = Nursing pup, no wrinkles

P3 = Nursing pup, blimp, black

P4 = Nursing pup, molting

P5 = Nursing pup, molted

PW = Prematurely weaned/undersized weaned pup (weaned <2 weeks

ago and <90 cm girth)

W = Weaned pup

Immatures

I = Immature

J = Juvenile

J1 = Juvenile I

J2 = Juvenile II

S = Subadult

S3 = Subadult III

S4 = Subadult IV

Adults

A = Adult

Unknowns

U = Seal of unknown size

Turtles
120

Adult Females and

immatures of both sexes Adult males

T = Turtle

T1 = Turtle, juvenile (<65 cm)

T2 = Turtle, subadult (65-80 cm)

T3 = Turtle, adult (>80 cm)

Only code the sex as known if the ventral is seen or if the seal is the mother

in a mother/pup pair, even if you "know" the sex because of the tag, bleach,

scars, or behavior.

SEX M = Male

F = Female

U = Unknown

BEACH POS. Locat

ion of seal or turtle

when observer comes

abreast of animal (e.g., if seal is seen in the water from a

distance and yet is on the beach when the observer comes abreast,

the seal is recorded as being on the beach). When recording malemale interactions (at Laysan and Lisianski Islands in 1997), make

a continuation line previous to the original line to indicate that

the seal changed beach position before you come abreast of it.

0 = animal floating or swimming in water (not included in census

tally but may be used for behavioral data or other analysis)

1 = on the beach

9 = on an offshore rock (not included in census tally)

X = data not taken

CONDITION It is assumed that condition is recorded for all seals (except

nursing pups) on census or atoll count. Always record the

condition of the mom and pup on their first sighting postpartum

and postweaning, regardless of data type. Always note condition

when recording a survival factor.

Condition codes:

M = medium

P = probably pregnant

F = fat

T = thin

X = data not taken

If the condition code is left blank during an atoll or census

count, condition is assumed to be medium.

ID DATA These fields can be used to record either a temporary or permanent

ID number. Use continuation lines to record both a temporary and

permanent number, or two or more temporary numbers. If the seal

is identified, it will not be counted twice on census. To link

two sightings of an unidentified seal during a survey (i.e., for a

cruiser moving ahead of you), assign it a temporary number in a

series reserved for unidentified seals, and code a 6 in the temp ?

field.

T/P Indicate whether the number in the subsequent field is a temporary or

permanent ID number.
121

T = temporary ID number (or bleach number)

P = permanent ID number

TEMPORARY ID NO. Record the temporary ID number (or bleach number) of seal if

known; right justified. This field may be used for any

temporary number. Use separate number series for bleach and

various types of temporary numbers. If a number is

incompletely read, use dashes as place-holders within the

number to indicate missing digits (e.g., incompletely read

bleach 152 may be coded -52, 1-2, or 15-).

? column:

0 = seal is definitely unmarked; can coexist with a temporary

number or with a bleach number if bleach hasn't taken yet or

the number has molted off.

1 = bleach is present, but the number is questionable.

4 = partially read bleach number completed from other data

5 = incompletely read bleach number, but partial data are

certain (if seal can't be identified by ID or Tag #).

6 = temporary number valid for this survey only, use for data

types C, A, B, or P (for unident. cruisers moving ahead of

you on census, etc.).

blank = number is certain and complete if present.

PERMANENT ID NO. Record the four-digit permanent ID number of seal if known

(put both the island-specific prefix and next digit in the

first box provided).

? column:

0 = seal is definitely not an IDed animal

1 = ID number is questionable

blank = ID number is certain and complete if present

TAG NO. The complete tag number if known; right justified. If a number is

incompletely read, use dashes as place-holders within the number

to indicate missing digits. Put the alpha prefix of the temple

tag (combined with tag ? column code = 5) if you can determine the

hole drilling pattern, but can't decipher the number (e.g., A--RT5

for a right tan tag with a 1983 drill pattern).

Record all tag sightings explicitly (i.e., both left and right tag

numbers) at least once during your stay. During the first weeks

of the field camp, note tag condition each time that a tag is

sighted. Once the majority of tags have been resighted, observers

can carry a list of tags/individuals that haven't been seen, and

only note tag condition if these tags/individuals are resighted.

Also carry a list of broken or lost tags so that you will be

aware, and can record, if a specific tag breaks or is lost during

the field season. When a pup is tagged, record the animal

handling event on the census data sheet, and record detailed

information (such as all tag numbers) on a Tagging/Handling card.

If a seal is identified via a tag, it is not necessary to

determine and enter its ID number on the census form. The ID

number can be determined by computer later.

L/R: Tag position

L = tag on left flipper

R = tag on right flipper

B = tags on both flippers (enter one tag number)
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COL:

Color code--see the Tag Sample Kit if unsure of the colors.

Temple tags Other tag types

Y = yellow (FFS) M = metal, Monel

T = tan/brown (Laysan) C = clear, PIT tag

G = green (Lisianski)

B = blue (Pearl & Hermes)

K = silver/gray (Kure)

R = red (Midway, Necker, Nihoa, Main Islands)

? column:

0 = seal is definitely not tagged on either flipper.

1 = seal is tagged, but the number is questionable.

4 = partially read tag completed from other data.

5 = incompletely read tag, but partial data are certain (if seal

can't be identified by ID or Temporary #).

8 = Tag lost/unreadable. Fill out tag position (L/R) and the

tag condition event with codes L or U. Complete the tag

number and color from other data before entry.

blank = Tag information is certain if present. Partial data

(either complete Tag #, position, or color not filled)

are OK and will be completed by computer if the seal

is identified by ID, Temporary #, or Tag #. The

computer will only fill blank fields, so an incomplete

Tag # must be completed by hand (use a "4" in the tag

? column).

MOLT Percentage of old pelage lost, optional for pups. However, for

weaned pups, record the % molt at time of tagging.

blank = no molting evident.

0-9 = 1 to 99% molted:

0 = molting, but less than 10%; 1 = 10-19%; ... 9 =

90-99%. The first record of a >2 molt is considered

the first day of true molt.

10 = 100% molted, freshly molted, required for the first

month after molt. Put both digits of the 10 in the

single box provided.

? column:

0 = seal is definitely not molting.

1 = seal is molting, but % molt estimate is questionable. May

or may not include an estimate in the molt column.

DISTURB The degree to which the seal may have been disturbed by

observer. Record disturbance every time a seal is disturbed,

regardless of your activity. The only exception is that you do

not need to record a disturbance for a seal that you are

handling.

0 = no disturbance, or seal merely raised its head or looked at

observer - If column blank, 0 is assumed

1 = seal vocalized, gestured, or moved <2 body lengths

2 = seal alerted to observer and moved >2 body lengths

3 = seal alerted to observer and fled into water

ASSOCIATION DATA Record detailed association data at Laysan and Lisianski

Islands in 1997. Don't record associations involving

turtles. If you wish to indicate that a seal was alone,

use the O behavior code. On a census or behavior patrol

data sheet no code in any of the association columns

means that the seal was alone, whereas on a regular

patrol data sheet no code may simply mean that no data
123

were taken. It is not necessary to put an O code for

each unassociated animal on census or during behavior

patrol at these locations because it will be filled in by

computer. If you are unable to record association data

on a census or behavior patrol at Laysan or Lisianski

Island for any reason, indicate this with an X for the

behavior code. Use continuation lines to record more

than one association.

An association should either be all blank or have the O, Z, or X behavior only (with no line number or distance),

or have a line number, a distance, and some behavior code

(other than O or X) all present. Don't record behaviors

of an animal after it has been disturbed by the observer.

All associations should be in pairs, i.e., between

animals on two different lines. If the behavior is

active, you should fill in the line numbers, distances,

and behavior codes for both animals involved in the

association. If the behavior is N or L, however, you may

record the association on only one of the lines, and the

entry/checking program will fill in the other line. When

recording an active behavior that requires a

corresponding code, the association line number should

refer directly to the line where the corresponding

behavior is coded (i.e., if the corresponding code is on

a continuation line, refer to that particular line, not

to the original line or a different continuation line).

Active associations

1) noted for all except behaviors between mother and nursing pup

2) must take place within 30 m of observer

3) subjects may be any distance apart

Spatial associations

1) noted as observer comes abreast of the subject

2) individual seals

- mother-pup pair (N): any distance

- all others (L): distances <10 m away; record two nearest

neighbors in straight line of sight; can be on opposite

sides of a log

LINE NO. Identity of the other seal in the association. Put its line

number here (note line number refers to within same census page

only).

DIST. Closest distance during behavior--both associated lines must have

the same minimum distance.

0 = body contact

1 = <2 m

2 = 2-5 m

3 = >5 m (>5 m but <10 m in the case of L behavior code)

BEHAVIOR Up to four behaviors may be recorded for each association, but L,

N, X, and O should not appear together with other behaviors.

Behaviors B and M require distance = 0. Behavior J requires

distance of 0 or 1. With the exception of Bites, Chases, Jousts,

and Mounts, only record repetitive, sequential behaviors once (for

example, if an animal approaches three times in a row, code one

A). If vocalizations occur, only code V once (whether or not they

are sequential).

1) individual seal

a) active behavior

A = approach/investigate/sniff/nudge
124

B = bite

B1 = bite, nip

B2 = bite, draws blood/breaks skin

C = chase

C1 = chase, <2 body lengths*

C2 = chase, >2 body lengths*

D = seal displaces another (see CONTEST RULES)*

F = flee/move away

F1 = flee/move away, <2 body lengths

F2 = flee/move away, >2 body lengths move away

J = joust

J1 = joust <30 s*

J2 = joust >30 s* spar/fight*

M = mount/attempted

M1 = mount/attempted mount <30 s

M2 = mount/attempted mount >30 s

P = play* (typically pup/immature behavior in the water)

R = submissive roll/present ventral

V = vocalize

Z = cruising. A/S4 male only behavior (actual sex may be

unknown). Does not require a line number reference to

another seal, but may have one)

b) spatial association (reciprocal association filled by computer

N = mother-pup pair (any distance), does not imply actual

nursing behavior. This is the only association

recorded between mother-pup pairs.

L = association by location only (distance <10 m apart, for

all except mother-pup pairs)

c) additional codes (Laysan and Lisianski 1997)

L1 = pair assoc.* A/S4 male actively defends an adult

female or immature of either sex (actual sex may be

unknown) or establishes a pair relationship with a

female or immature after displacing another male.

Code the L1 relationship before and after contest if

displacement occurs.

Q = loser*

W = winner*

Y = tie*

Note: codes Q, W, and Y are used for A/S4 male-male contests only,

although the actual sexes may be unknown (in which case record as

though they were known to be males); see the attached CONTEST

RULES.

* requires a corresponding code on the line of the associated seal

Code Corresponding code

C, C1, C2.............F, F1, or F2

D.....................F, F1, or F2

J, J1, J2.............J, J1, and J2 respectively

P.....................P

L1....................L1

Q.....................W

W.....................Q

Y.....................Y

2) nothing nearby

O = no behavior or association

3) no data

X = no association data recorded on Census or Atoll Count
125

NOTES--There is room to code two different notes. Always use the first column

first. Code an H if you have handwritten notes on the observation. Put

handwritten notes on the bottom of the census form, labeled by line number.

If more than two note codes apply, use continuation lines.

A = artwork (scars drawn) - attach drawing, labeled with date,

computer page number, and line number

B = birth, 1st sighting postpartum (mom and pup)

G = seal is green with algae

H = handwritten notes

M = marked, bleach number 1st applied/reapplied post-molt

W = weaning, 1st sighting postweaning (pup)

X = pup exchange, 1st sighting after exchange (mom and pup)

Y = disturbance is to "bystander" seal during non-survey activity such

as tagging, bleaching, instrumenting, etc. This includes all

"hands on" research, even if the attempt was unsuccessful.

FOR DATA TYPE "T", STATUS OF NON-ACTIVE TAGS:

F = found

R = recovered from seal in hand

EVENT These columns are used to record a variety of data. The codes used will

depend upon the type of event that you wish to record. Left justify

your coding:

TYPE CODES CONTENT

COLUMN

F = survival factor ONLY RECORD RESIGHT OF A SURVIVAL FACTOR

AS AN EVENT IF THERE ARE IMPORTANT

CHANGES TO DOCUMENT, SUCH AS A NEW

WOUND, HEALING, DEATH, ETC.

1-3 Survival Factor number

4 Factor Type. If seal is dead, always

record factor type "D" on ORIGINAL LINE.

For mobbings/harassments, always code

a census entry with factor type "M" for

the victim at the beginning and end of

the incident. Otherwise, you only need

to record the most appropriate factor

type if more than one applies.

D = death

W = wound

E = entanglement

V = very thin (emaciated)

I = illness/abnormal

M = mobbing/harassment/post-mobbing

aggregation

O = other

5 Participant type (for mobbings/

harassments only)

V = victim/subject

M = male aggressor

H = handling of wild seal FOR SEAL CAPTURES OR RELEASES, RECORD

DETAILS ON EITHER THE CAPTURE OR RELEASE

FORM. OTHERWISE, RECORD DETAILS ON THE

TAGGING/HANDLING CARD.

1 Handling type

T = tagging (w/ restraint)

M = measuring (includes weighing)
126

A = all (both tagging and

measuring)

R = remote tagging

D = disentangle

I = instrument

B = bleeding

C = take into captivity

F = free from captivity

O = other

TYPE CODES CONTENT

COLUMN

P = photo RECORD IMPORTANT DESCRIPTIONS AND ANY

NON-SEAL PHOTOS IN HANDWRITTEN NOTES,

AND TRANSFER TO THE PHOTO COMMENT FORM.

1 Type of photo

S = slide

P = print

2-3 Roll number (pad with zeros)

4-5 Frame number (pad with zeros)

6 Side

L = left lateral or flipper

R = right lateral or flipper

D = dorsal side

V = ventral side

B = both (used for rear flippers

only)

X = other, describe in handwritten NOTES

7 Part

H = head

A = anterior body (neck and

shoulders)

M = midbody (behind foreflippers

and before posterior)

P = posterior body (behind midbody

and before rear flippers)

F = foreflipper; write whether

dorsal/ventral in comments

R = rearflipper; write whether

dorsal/ventral in comments

O = overall view of a particular

side

X = other, describe in comments

8 Purpos

e

I =

iden

tifi

cati

on

F = survival factor (link with

survival factor EVENT using

continuation lines)

X = other, describe in comments
127

TYPE CODES CONTENT

COLUMN

T = tag condition 1 Web

A-D = from inner (medial) to outer web

E = ankle

P = posterior

U = unknown

2 Side of tag--the dorsal tag side is on

the dorsal flipper surface unless the

tag is reversed. For Temple Tags, the

dorsal side is the bigger side; for

Metal (Monel) tags, the dorsal side is

the "male" side. For PIT tags, code the

side as B (both).

D = dorsal

V = ventral

B = both

U = unknown

3 Condition, code U (unreadable) if cannot

use tag to ID seal (i.e., if broken so

number gone). Also code U for a PIT tag

if you completely scan for it but get no

reading. Combine the L or U codes with

the tag questionable code of 8. Code

more than one condition using

continuation lines.

B = broken

F = faded color

G = good

L = tag lost

N = no/partial resin

O = other

P = pulling out

U = unreadable

V = tag side reversed

W = no. worn/abraded
128

CONTEST RULES

1. Size class collapse for contests: all subadults = adults (both sexes)

2. Definition of pair type (depends on associate of adult male):

• Pair type #1: adult male with adult female (L1)

• Pair type #2: adult male with juvenile or pup of either sex (L1)

• Pair type #3: single adult male not pair type #1 or #2

3. Definition of a male-male contest (must conform to at least one condition

below):

• Distance between males = 0

• Either adult male vocalizes (V) or performs a C, D, or J

• If cruiser approaches to beach position 1, regardless of other

behaviors

4. Definition of winner or loser adult male (Even if the "winner" is not

aware that the other seal flees, if that seal fled in response to a

vocalization, then code the fleeing seal as the loser (Q) and the other

seal as the winner (W)):

Case Winner (W) Loser

(Q)

Tie (Y)

Paired Male vs. Single Male:

(#1 or #2 vs. #3)

i) Original Single

Male if has D

ii)

Original Paired

Male otherwise

Has F No Ties

No Ties

Male Paired with Adult Female

vs. Male Paired with Juvenile

Seal:

(#1 vs. #2)

i) Original Male

Paired with

Juvenile if has D

ii)

Original Male

Paired with Adult

Female otherwise

Has F No Ties

No Ties

Paired Male vs. Paired Male

where both pairs are same

type:

(#1 vs. #1 or

#2 vs. #2)

Has D Has F Tie if no

D

Single Male vs. Single Male:

(#3 vs. #3)

Has D or C Has F Tie if no

D or C