bluuebunny/crossref_metadata_2025_split huggingface dataset:
NORTH PACIFIC HUMPBACK WHALE SONGS: A COMPARISON OF SOUTHEAST ALASKAN FEEDING GROUND SONGS WITH HAWAIIAN WINTERING GROUND SONGS
Authors: McSweeney D. J. , Chu K. C. , Dolphin W. F. , Guinee L. N. 
Published: August 2006

AbstractHumpback whales sing long, complex songs on their wintering grounds. On 25 August 1979 and 3 September 1981, we made recordings of humpback whale songs in southeastern Alaska, showing that humpback whales also sing on the summer feeding grounds. Both these Alaskan samples are songs in that they are repeating cyclical sound patterns and follow the known structure for humpback whale song. The Alaskan songs contain all the same material sung in the same order as that heard off Mexico and Hawaii in the surrounding wintering seasons. However, song, theme and some phrase durations are abbreviated in the Alaskan songs. The recording of these two songs represents the full sample of song recorded from 155 days over five years of attempting to record humpback whale song in Alaskan waters.
THE DISTRIBUTION, ABUNDANCE AND SELECTED PREY OF THE HARBOR SEAL,PHOCA VITULINA CONCOLOR, IN SOUTHERN NEW ENGLAND
Authors: Payne P. Michael , Selzer Lawrence A. 
Published: August 2006

AbstractThe seasonal distribution and abundance of harbor seals occurring south of Maine were documented by counting the number of seals at traditional haulout locations. The average number of seals counted during each survey in Massachusetts and New Hampshire was 3,560 ± 255 (95% CI), 1983–1987. The maximum number of seals counted on any individual survey was 4,736 individuals. Fifty percent of all the surveys since January 1985 have resulted in counts greater than 4,000 seals reflecting a 27% increase in the abundance of seals in our study area since that date. Seventy‐five percent of the seals in southern New England are located at haulout sites on Cape Cod and Nantucket Island. The largest aggregation of seals in the eastern United States occurs mid‐winter at Monomoy Island and adjacent shoals. A single high count of 1,672 seals occurred at this site during the study period. An additional 271–374 seals were also counted in Rhode Island, Connecticut and eastern Long Island Sound during surveys conducted in March 1986 and 1987.The American sandlanceAmmodytes americanuswas the single dominant prey item of harbor seals in waters adjacent to Cape Cod based on the modified frequency of occurrence of each prey species in scat samples collected from three haulout sites on Cape Cod between 1984–1987. During January and February sandlance was the near exclusive prey item at Monomoy (99%,n= 80). During March and April, the frequency of Atlantic herringClupea harengusincreased in the scat samples at this site. Regional differences in the diet of seals reflect distinct prey communities throughout the study area. Since 1986, the percent occurrence and importance of sandlance in the diet of seals has decreased, reflecting an overall decrease in abundance of this prey species in waters adjacent to Cape Cod. In spite of fluctuations in abundance, and regional differences in the diet of seals throughout the study area, sandlance still comprised a minimum 55% of the total prey species of harbor seals throughout the study area.
SEX DETERMINATION OF THE CALIFORNIA SEA LION (ZALOPHUS CALIFORNIANUS CALIFORNIANUS) FROM CANINE TEETH
Authors: Lowry Mark S. , Folk Roberta L. 
Published: August 2006

AbstractSize of canine teeth from California sea lion (Zalophus californianus californianus) carcasses is shown to be useful in determining the sex of animals which have missing genitalia or which are otherwise of unknown sex. A total of 267 canine teeth from carcasses of 68 males and 43 females were measured along five axes. Of root and crown measurements of upper and lower canines, males and females overlapped only in root thickness of upper canines. A multivariate ANOVA showed a significant difference in the size of canines between upper and lower canines, and between males and females. Stepwise discriminant analysis produced discriminant functions for upper and lower canines for determining sex of unknown‐sexed California sea lions. A separate set of canine teeth from 39 male and 49 female California sea lions was correctly classified without prior knowledge of sex by visual inspection and by the two discriminant functions.
TOOTH WEIGHTS OF JUVENILE MALE NORTHERN FUR SEALS, CALLORHINUS URSINUS
Authors: Baker Jason D. , Fowler Charles W. 
Published: August 2006

AbstractTooth weight and body length of juvenile male northern fur seals, Callorhinus ursinus, collected on St. Paul Island, Alaska, from 1948 to 1984 were compared. The relationship between these variables was investigated for individual and combined age classes. A density‐dependent increase in mean tooth weight occurred during a decline in fur seal abundance. Consistent, though poorly understood, differences in tooth weight were found among males associated with different rookeries (breeding grounds). Storing the teeth for long periods may affect the weights, but such effects, if any, are too small to account for the changes observed.
FATTY ACID COMPOSITION OF FATS FROM THE URUGUAYAN FUR SEAL (ARCTOCEPHALUS AUSTRALIS ZIMMERMANN)
Authors: Grompone Maria A. , Sienra B. , Quilez J. L. 
Published: August 2006

AbstractThe composition and properties of commercial oil collected from Uruguayan fur seals (Arctocephalus australis Zimmermann) during 1985, 1986 and 1987 are reported. Oil recovered from some organs (kidney, heart, liver) and blubber were also analyzed. All have compositions similar to oils from other marine animals in commercial use, containing high percentages of long chain and polyunsaturated fatty acids.
A MORPHOLOGICAL CONSIDERATION OF THE RELATIONSHIPS OF PINNIPEDS TO OTHER CARNIVORANS BASED ON THE BONY TENTORIUM AND BONY FALX
Authors: Nojima Takao 
Published: August 2006

abstractThe close relationships of pinnipeds to other carnivorans were studied based on morphological characteristics of the bony tentorium (BT) and bony falx (BF) of carnivorans. It appears to be an important characteristic of the Carnivora that the clear BT is present in almost all species including pinnipeds. The BF is present in all species of pinnipeds, and only in the genus Ursus among fissipeds observed.The parietal bone of all otariids and odobenids observed shows an extremely characteristic form as compared with other carnivorans. The sagittal and squa‐mous borders of the parietal bone of these groups are bridged by a thin bony plate which forms large portions of the BT and BF. In phocids, the aspects of the BT and BF vary among species, but are apparently distinct from those of otariids and odobenids.The BT of carnivorans can be divided into four types which appear to be useful for classification of the Carnivora. On the basis of the BT and BF form, the Otariidae and Odobenidae appear to have a specific sister relationship to the Ursidae, while the Phocidae appears to have dose affinities to the Mustelidae. Morphological differences of the BT and BF among pinnipeds strongly support the diphyletic origin of pinnipeds.
BLUE WHALE (BALAENOPTERA MUSCULUS)DISTRIBUTION IN THE EASTERN TROPICAL PACIFIC
Authors: Reilly Stephen B. , Thayer Victoria G. 
Published: August 2006

AbstractThe distribution of blue whales, Balaenoptera musculus, in the eastern tropical Pacific (ETP) was analyzed from 211 sightings of 355 whales recorded during research vessel sighting surveys or by biologists aboard fishing vessels. Over 90% of the sightings were made in just two areas: along Baja California, and in the vicinity of the Costa Rica Dome (a large, stationary eddy centered near 9°N, 89°W), with the rest made along the equator near the Galapagos islands, the coasts of Ecuador and northern Peru. All sightings occurred in relatively cool, upwelling‐modified waters. Because these areas are the most productive parts of the ETP, and have relatively large standing stocks of euphausiids, it seems possible that blue whales select low latitude habitats which permit foraging. The waters off western Baja California were occupied seasonally, with a peak in sightings coinciding with the spring peak in upwelling and biological production. The Costa Rica Dome area was occupied year round, suggesting either a resident population, or that both northern and southern hemisphere whales visit, with temporal overlap. The modal group size was one for all areas and seasons, but the frequency of groups with two or more whales was significantly higher in sightings made near the Galapagos Islands and the coast of Ecuador and northern Peru.
DENSITY DEPENDENT GROWTH IN NORTH PACIFIC SPERM WHALES
Authors: Kasuya Toshio 
Published: August 2006

AbstractData from the North Pacific sperm whale (Physeter catodon Linnaeus, 1758) fishery were examined for a possible density dependent change in growth during 40 yr harvesting after World War II. Early in this period males from the eastern stock were 16.8 m or less in length. By the early 1970s the largest males in the catch exceeded 16.8 m in length and reached 18.9 m in the late 1970s. The proportion of males measuring over 16.8 m, among sexually mature males (≥14.0 m), increased from 0 to >20% during the 1970s. Increases in the maximum size of males were possibly preceded by a change in the frequency distribution of body lengths in the middle 1960s when only 10% of the postwar catch had been taken. Testis weights suggested an increase in body length at sexual maturity. Two of the three putative North Pacific stocks showed similar growth changes. Adult males taken in the Bering Sea did not show such changes during the exploitation which ended in 1972 because of overfishing. Females showed no detectable change in body size. It is concluded that: (1) density dependent effects on male growth are greater before sexual maturity than after it, (2) males may show density dependent changes even at a population level above 90% of the carrying capacity, (3) polygynous males acquire more mates and realize higher reproductive success because of increased body size, and (4) females appear to maximize production by maturing earlier and shortening calving intervals in response to density change.
ACOUSTIC REFLECTIVITY OF NETS: IMPLICATIONS CONCERNING INCIDENTAL TAKE OF DOLPHINS
Authors: Au WhitlowW. L. , Jones Linda 
Published: August 2006

AbstractSonar target strength measurements of several types of nets and associated gear were made using simulated dolphin echolocation signals. The different types of nets included (a) standard commercial monofilament gillnet used in the salmon mothership fishery, (b) prototype hollow core monofilament net, (c) Macah tribal cord setnet, and (d) multifilament nets. Target strength measurements were made at four angles of incidence, 0° (normal to net), 15°, 30°, and 45°. The standard gillnet had the smallest target strength which was relatively independent of the angle of incidence. The target strength based on the peak‐to‐peak values of the echoes varied from –59 to – 62 dB. Using echo energy within the integration time of Tursiops truncatus, the target strength was found to be between – 54 and –59 dB. Biosonar detection ranges for different sea state conditions were estimated using the noise‐limited form of the sonar equation and target detection data obtained for Tursiops truncatus in Kaneohe Bay, Oahu, Hawaii. The results suggest that an echolocating dolphin should be able to detect a gillnet at ranges long enough to avoid entanglement, even in sea state 6 conditions. Several possibilities for the seeming inability of dolphins to detect gillnets are discussed.
MODIFYING GILLNETS TO REDUCE ENTANGLEMENT OF CETACEANS
Authors: Dawson Stephen M. 
Published: August 2006

AbstractTo reduce the number of cetaceans caught incidentally in gillnets, two forms of acoustic modifications have previously been proposed. These modifications seek to make gillnets more obvious to cetaceans so they can avoid them, and include making gillnets more reflective to cetacean sonar and placing active sound emitters in the nets. I discuss the relationship between sonar and net entanglement, and address the assumptions and logic of net modification strategies. I argue that neither strategy is likely to be effective, and that reductions in the number of cetaceans killed in gillnets are best achieved through the closure of specific areas to gillnetting.
HYDROSTASIS IN THE SIRENIA: QUANTITATIVE DATA and FUNCTIONAL INTERPRETATIONS
Authors: Domning Daryl P. , de Buffrénil Vivian 
Published: August 2006

ABTRACTIt has long been assumed that the heavy bones and horizontal lungs of sirenians are adaptations for maintaining neutral buoyancy and horizontal trim. These assumptions are examined in the light of detailed measurements of skeletal weight distribution in the Florida manatee (Trichechus manatus latirostris), measurements of the positions of body and skeletal centers of gravity in the Amazonian manatee (T. inunguis), and available data on lung morphology in sirenians. The detailed arrangement of bones, muscle masses, and viscera in a sirenian (T. inunguis) is illustrated in cross sections for the first time. The hypotheses that skeletal weight is appropriately distributed to serve as hydrostatic ballast, and that the lungs are properly designed to help maintain horizontal trim, are confirmed. We suggest that selection for maintenance of trim and maximization of turning moments of the flippers may help account, respectively, for hindlimb loss and shortening of the neck in both sirenians and cetaceans. We recommend that the term “pachyostosis” be used to refer only to thickening of bones regardless of their density; that “osteosclerosis” be used for the replacement of cancellous with compact bone; and that “pachyosteosclerosis” be used for the joint occurrence of these conditions. Pachyosteosclerosis in sirenians, which may be brought about during ontogeny by mechanisms involving thyroid and parathyroid hormones, is fully normal and adaptive in this order and in no sense “pathological.”
A NEW SPECIES OF BEAKED WHALE MESOPLODON PERUVIANUS SP. N. (CETACEA: ZIPHIIDAE) FROM PERU
Authors: Reyes Julio C. , Mead James G. , Waerebeek Koen Van 
Published: August 2006

Abstract Mesoplodon peruvianus, a new species of beaked whale, is described on the basis of ten specimens which have either stranded or been captured between 11°12′S and 15°19′S latitude along the coasts of the provinces of Lima and Ica, south central Peru. This is the thirteenth living species of Mesoplodon recognized in the world's oceans. The animals that were examined were uniformly gray above, shading to lighter gray below. This whale is the smallest species of Mesoplodon (maximum body length 3.72 m) and is characterized by its teeth, which are small (31 to 65 mm long), ovate in cross section, and positioned 2.5% to 8.4% of the mandibular length from the anterior extremity, and posterior to the mandibular symphysis.
ACCURACY OF AGE DETERMINATION IN THE GREY SEAL HALICHOERUS GRYPUS OF EASTERN CANADA
Authors: Mansfield A. W. 
Published: August 2006

AbstractThe ages of 82 grey seals of known age from 1 to 10 yr were determined from growth layer groups in the cementum, readily seen in longitudinal sections 150 μm thick viewed under transmitted light. The sample of teeth was read five times in a series of blind replicates.With only one reading, an accuracy of 84% was achieved. This increased to 93% on the basis of three readings but improved only marginally to 94% when all five readings were considered. Accuracy was best in the middle range of ages (3–6 yr) which are the critical years for estimating age‐specific reproductive rates in population models.
CUTANEOUS RIDGES IN ODONTOCETES
Authors: Shoemaker P. A. , Ridgway S. H. 
Published: August 2006

AbstractCutaneous ridges are present at the surface of the skin in many odontocetes, and although often quite faint, may be observed with the naked eye. We have taken surface impressions and measured the ridges of individuals of seven odontocete species, and observed cutaneous ridges on three additional species. In the delphinids and the one Physeter neonate studied, spatial periods of the ridges varied from 0.4 mm–1.7 mm and trough‐to‐peak heights from less rhan 10μm to about 60μm. Two Delphinapterus (monodontids) had ridges significantly larger than the Physeter and most delphinids, with spatial periods of 1.9–2.4 mm and heights 80–120 μm. We found the ridges distributed over much of the surface of the body, but relatively faint or absent on most of the head, the control surfaces, and the ventral region in some species. In all of the animals we observed, the ridges ran in an approximately circumferential direction around the body trunk rostral to the dorsal fin or mid‐body area, but varied somewhat in direction in the caudal region and in other isolated areas. While the function of the cutaneous ridges has not been established, we speculate that they may play some role in tactile sensing, in the hydrodynamic characteristics of an animal, or both.
PRECISE BIRTH TIMING IN CAPTIVE HARBOR SEALS (PHOCA VITULINA) AND CALIFORNIA SEA LIONS (ZALOPHUS CALIFORNIANUS)
Authors: Temte Jonathan L. 
Published: August 2006

AbstractThe absolute and relative precision of birth timing was assessed in 27 captive harbor seals and 30 captive California sea lions. Data were obtained from zoos and aquaria and only adult females with at least three live births were selected for analysis. Individuals of both species demonstrated very high absolute precision with narrow ranges of birth dates and small standard deviations of the individual mean birth dates. In addition, with the exception of one sea lion, no temporal trends for earlier or later birthing were found. Whereas marked differences in birth timing were found among individual harbor seals, these relative differences tended to disappear when subspecies affiliation and location were taken into account. Moderate inter‐individual differences were also found among the California sea lions, but these differences persisted following the partitioning of adult females by location.The absolute precision in birth timing strongly suggests that environmental regulation of birth timing occurs via a highly precise cue, such as photoperiod. The relative differences among individuals may indicate that birth timing in pinnipeds has a heritable component, and hence may evolve in response to natural selection, thus allowing adaptation of the pupping season to specific seasonal environments.
DISTRIBUTION PATTERNS OF INDIVIDUALLY IDENTIFIABLE WEST INDIAN MANATEES (TRICHECHUS MANATUS) IN FLORIDA
Authors: Reid JamesP. , Rathbun Galen B. , Wilcox J. Ross 
Published: August 2006

AbstractPhotographs of distinctively scarred manatees (Trichechus manatus) were taken at aggregation sites throughout Florida and assembled into a catalog for identifying individuals. Resightings of known manatees in different years or at different locations enabled us to document site fidelity and long‐distance movements. Of the 891 individuals included in the catalog as of August 1986, 470 (53%) were resighted at least once. We documented 219 cases of seasonal returns to specific aggregation sites and 98 instances of movements between areas. Movements in excess of 820 km were documented for individuals on the east coast of Florida. Rapid movements south during early winter, as well as northerly spring movements, verify a seasonal migration pattern for many individuals along Florida's east coast. The wide‐ranging migratory habits of manatees in Florida must be considered if meaningful management strategies are to be developed and implemented.
THE OCULAR SECRETIONS OF THE BOTTLENOSE DOLPHINTURSIOPS TRUNCATUS
Authors: Young N. M. , Dawson W. W. 
Published: August 2006

AbstractA viscous ocular secretion streams from the eyes of bottlenose dolphins,Tursiops truncatuss, removed from the water. The chemical composition and environmentally adaptive implications of this substance continue to perplex curators and scientists. Secretions from three dolphins were examined for deviations from literature values for normal human and terrestrial mammalian tear film components. Osmolality (x̄= 470 mOsm/kg), pH (x̄= 8.44) and glucose (x̄= 26.58 mg/100 ml) were significantly greater than human and terrestrial mammalian tear film values; while lysozyme (x̄= 0.005 mg/ml) and total cholesterol (x̄= 0.17 μg/μ1) were significantly less. Refractive index, sodium ion concentration, and potassium tear to plasma ratios in the dolphin ocular secretion did not deviate significantly from human or terrestrial mammalian tears. Electrophoresis of dolphin tears yielded four major protein bands (probably lactoferrin, serum albumin, teat specific prealbumin, and lysozyme) and high molecular weight glycoproteins similar to human tears. The chemical composition of theT. truncatusocular secretion suggests that the circumorbital conjunctival gland may be analogous (relative to refractive index, electrolytes, and component protein) to the terrestrial lachrymal gland. At the functional level theT. truncatusocular secretion may reduce hydrodynamic resistance on the cornea and protect it from bacterial invasion.
ANALYSIS OF SWIM VELOCITIES DURING DEEP AND SHALLOW DIVES OF TWO NORTHERN FUR SEALS, CALLORHINUS URSINUS
Authors: Ponganis Paul J. , Gentry Roger L. , Ponganis Edward P. , Ponganis Katherine V. 
Published: August 2006

AbstractSwim velocities at 15‐sec intervals and maximum depth per dive were recorded by microprocessor units on two “mixed diver” adult female northern fur seals during summer foraging trips. These records allowed comparison of swim velocities of deep (>75 m) and shallow (<75 m) dives.Deep dives averaged 120 m depth and 3 min duration; shallow dives averaged 30 m and 1.2 min. Mean swim velocities on deep dives were 1.8 and 1.5 m/sec for the two animals; mean swim velocities on shallow dives were 1.5 and 1.2 m/sec. The number of minutes per hour spent diving during the deep and shallow dive patterns were 11 and 27 min, respectively.Swim velocity, and hence, relative metabolic rate, did not account for the differences in dive durations between deep and shallow dives. The long surface durations associated with deep dives, and estimates of metabolic rates for the observed swim velocities, suggest that deep dives involve significant anaerobic metabolism.
THERMAL INFRARED RADIATION FROM FREE LIVING WHALES
Authors: Cuyler L. C. , Wiulsrød R. , ØRitsland N. A. 
Published: August 2006

ABSTRACTAs part of a search for new detection techniques, and for obtaining information on whale surface temperatures, an Agema Thermovision 880 thermal imaging system was used to detect thermal infrared radiation from whales. The study took place along the northern coast of Norway and the northwest coast of Svalbard (68° to 80° N latitude). The emphasis of the study was on minke whales, but humpback, fin, blue and sperm whales were also observed. The apparent radiation temperature was strongly dependent on sea conditions, signal angle, and atmospheric interference; detection depended thus upon weather. During the study, sea surface temperatures varied as much as 7°C but the sea and minke whale body trunk surfaces were usually within 0.0° to 0.1°C of each other. The other species observed had temperature differences of 0.0° to 1.0°C relative to the sea surface. Temperature differences between sea water and whale appendages ranged from 0.0° to 6.0°C. The indicated maximum difference between sea water and blow (i.e., expired air) was 4.0°;C, while the maximum difference for the blowhole was 4.1°C. The results from all whales observed support the belief that the main body trunk is normally not a heat window, this function being reserved for the appendages. However, the results also indicate a regulated dermal blood flow determining heat loss from the body trunk. Detection of whales by thermal infrared radiation from the body trunk appears unreliable; in contrast, the blow and blowhole provided a consistent positive signal with apparent temperature differences to the surroundings ranging from 0.2° to 4.1°C.