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Observations of feeding and ventilatory behavior of individual fin whales (Balaenoptera physalus) were made from various vessels during the months of May - September, 1981-87, in the waters off eastern Long Island, N.Y., U.S.A.. Intervals between blows were measured and recorded to the nearest second. Information about behavior was recorded, as were location, depth, and surface temperature at sounding dives. Animals observed feeding at the surface were noted as such, all others were considered non-surface feeding. Data were compiled by individual, month, year, and analyzed for mean interblow interval during surface activity bouts; mean dive duration; and overall mean blow interval.
Overall mean blow intervals (± s.e.) of 47.89 ± 0.81s for feeding (n = 10411), and 57.92 ± 0.97s for non-surface feeding animals (n = 11024), differed significantly (Mann-Whitney U, p < .001). Interblow intervals for surface activity bouts (± s.e.) of 12.29 ± 0.05s for feeding (n = 7894), and 13.58 ± 0.06s, for non-surface feeding animals (n = 8187), also differed significantly (Mann-Whitney U, p < .001), as did mean dive duration (159.53 ± 2.16s, n = 2517, for feeding animals; 185.86 ± 2.53s, n = 2837, for non-surface feeding animals). Yearly comparisons of blow intervals between feeding and non-surface feeding animals during surface activity bouts yielded significant differences for each year except 1981, while comparisons of dive durations yielded significant differences for all years except 1981, 1982, and 1985.
(1, 2, 4) Long Island University, Southampton College, (3, 5) Coastal Research and Education Society of Long Island, Inc.
Surveys of fin whales, (Balaenoptera physalus) were conducted during the months of May through September, from 1979 through 1996, off Long Island, New York. Surveys primarily occurred aboard whale watching vessels. When possible, individual identification photographs were collected on the cruises. Photographs from 1981 through 1988 were compared for matches of individuals based upon the technique described by Agler et al. All identification type photographs were entered into a computer database to facilitate a more rapid matching of individuals. Animals were keyed into the database based upon dorsal fin type, chevron, and/or nicks and scars. Initial matching was based upon these features. Final matches were made by manually examining each slide and matching at least 5 major features for each whale.
Individual fin whales were found to occupy the region on a recurring basis over numerous years. In some instances occupancy was repetitive on an annual basis, while in other instances gaps of one or more years occurred. Individual fin whales were found to occupy the region for a period of up to 9 weeks, however, many animals were not photographed on a continuous or daily basis. This may not be indicative of movement from the area as surveys throughout the entire occupancy area were often not possible aboard the platform vessel. Residency diagrams presented with this study demonstrated a clear preference to return to the region over a period of years.
In 1987, a very large number of new animals were seen in the area, as some of the largest numbers of whales found in the region were observed. In our analysis, this year had to be considered anomalous based upon the extremely large number of whales found in the region. The large number of whales seen has not been repeated since that time.
The resighting rate indicates that a significant number of animals seen annually in the region were previously sighted individuals. Based upon the high resighting rate and the long term annual recurrence of individual fin whales, this area may be a significant seasonal residency site. However, animals were not always seen in the same areas either within one year or over a period of years. Resightings of whales indicate a use of the whole area and not a specific trend to one site. Consequently, movement throughout the area would be expected based upon our analysis.
Forestell, P.R., Paton, D.A., Rodda, P. & Kaufman, G.D. 2001 1231: Observations of a hypo-pigmented humpback whale, Megaptera novaeangliae, off east coast Australia: 1991-2000.Memoirs of the Queensland Museum 47(2): 437-450. Brisbane. ISSN 0079-8835.
In 1991 an apparently all-white humpback whale was observed and photographed from a shore-based observation platform in Byron Bay, NSW, Australia. The following year, the same animal (based on comparison of photographs of dorsal fill shape) was observed and extensively photographed in Hervey Bay, Queensland. Since then, more than 50 reports of white whale sightings have been obtained with reports in every year except 1997. The whale appears to be an albino and is the only documented occurrence of an all-white humpback whale. Sightings of this unusual animal provide important information on the migratory characteristics of humpback whales along the east coast of Australia. We investigated all known reports of a white whale from 1991-2000 and applied a scale of verifiability to each report. We plotted the location and time of each reliable sighting and summarised the range, rate of movement, social patterns and annual changes in migratory characteristics based on these reports. We present evidence that the white whale is now an adult male and relate its movements to what is known about male humpback whales from other studies.
GARRIGUE, C., FORESTELL, P., GREAVES, J., GILL P., NAESSIG P., PATENAUDE, N. M. AND. BAKER, S. C. 2000. Migratory movements of humpback whales (Megaptera novaeangliae) between New Caledonia, East Australia and New Zealand. Journal of Cetacean Research and Management 2(2):111-115 .
'Discovery’ marks and their recoveries from humpback whales
in the southwest Pacific provide no evidence of migratory interchange between
wintering grounds in New Caledonia and migratory corridors~ off east Australia (Moreton
Island) and New Zealand, or wintering grounds in Tonga. To provide further
insight into the migratory connections among these regions, images of 169
individually-identified humpback whales from New Caledonia were compared with
the published catalogues of Australian (n = 1,088), Tongan (<i>n</i> = 78) and
New Zealand (<i>n</i> = I) humpback whales. Four of the New Caledonian humpbacks
were found to have migrated past east Australia and one past New Zealand in
separate years. No movement was found between New Caledonia and Tonga. These
data provide the first photographic information on exchanges between regions of
the southwest Pacific. Reviewed in light of historical records, these data also
highlight the necessity for further research in the South Pacific region to
resolve the question of the proposed segregation of the Southern Hemisphere
Group V stock into an eastern group (New Zealand and the Pacific Islands) and a
western group (east Australia).</p>
Molly Lutcavage1, Russell Andrews2, Anders Rhodin3, Samuel Sadove4, Carol Rehm Conroy5,Hector Horta6
New England Aquarium, Central Wharf, Boston, MA, 02110 USA
Dept. of Zoology, University of British Columbia, Vancouver, BC Canada
Chelonian Research Foundation, Lunenburg, MA, 01462 USA
Tradewind Associates, Box 361, Jamesport, NY 11947 USA
Operative Services, Boston Medical Center, Boston, MA 02112 USA
Department of Natural Resouces, Fajardo, Puerto Rico
Movements of eleven leatherback sea turtles nesting in Culebra and Fajardo, Puerto Rico, were determined with directly attached time depth recorders (ST-TDR, 6 turtles) and pop-up archival satellite tags (5 turtles). Our main objective was to test the feasibility of using implanted titanium bone anchors (used in humans) to secure both tag types directly to the turtle’s carapace. Most ST- TDR duty cycles were set on nearly continuous transmission to maximize early data return. Attachment periods ranged from four days to over six months, the latter exceeding the expected life-span of the ST-TDR’s battery. Some turtles headed directly offshore, five bearing NW, and three to the E/NE. One of these turtles was located off North Carolina when transmissions ceased. One turtle moved directly NE, traveling over 4500 km to the Azores front via the mid-Atlantic ridge. At least four turtles returned to nest, but their tags were the earliest tags shed, suggesting that they may have been dislodged by mating activities. Daily geolocation estimates were obtained from popup archival tags while they remained on the turtles. Our results indicate that this nesting assemblage disperses to widely separated Atlantic regions. Simple modifications of our direct attachment methodology should allow us to greatly extend tracking duration.
David P. Reynolds1 and Samuel S. Sadove2,3
1. Department of Bioscience and Biotechnology, Drexel University, Philadelphia, PA 19104;
2. Coastal Research and Education Society of Long Island, Inc
3. Puffin Consulting Inc., PO Box 361, Jamesport, NY, 11947
Inshore embayments along the eastern Atlantic seaboard appear to provide important summer foraging habitat for juvenile sea turtles. The occurrence of sea turtles is seasonal in the temperate waters around Long Island, New York. Sea turtles regularly caught in commercial fishing gear (pound nets) in this area are loggerhead (Caretta caretta), Kemp's ridley (Lepidochelys kempi) and green (Chelonia mydas) turtles. These captures are a result of an ongoing program with commercial fishermen.
Upon capture, straight carapace length (SCL), width, and mass were measured. We tagged turtles with either a Passive Integrated Transponder (PIT) tag or a Monel Tag. All data was recorded for the New York Sea Turtle Stranding and Salvage Network and the NMFS Cooperative Marine Turtle Tagging Program. We compared the variance of SCL for loggerhead, Kemp's ridley and green sea turtles. An ANOVA of SCL showed no significant difference for 1986 to 1996 for loggerhead (p = 0.5525), Kemp's ridley (p = 0.5584) and green (p = 0.3492) sea turtles. Straight carapace lengths for these loggerhead (mean = 49.4, SD = 1.34, n = 233), Kemp's ridley (mean = 30.2, SD = 1.43, n = 107), and green (mean = 32.2, SD = 4.54, n = 80) sea turtles indicate that they were juveniles.
Earlier studies of migration and diets of Kemp's ridleys and loggerheads in New York waters used specimens collected by pound nets. The reported means of SCL in previous studies were similar to those found in this analysis. This study indicates that there has been no significant change in mean SCL of three species of sea turtles over a 10-year period.
David P. Reynolds1 and Samuel S. Sadove2,3
1 Marine Science Program, Southampton College/LIU, Southampton, NY 11968
2 Puffin Consulting Inc., PO Box 361, Jamesport, NY 11947
3 Coastal Research and Educational Society of Long Island, Inc
Sea turtle incidence is seasonal and considered common for the temperate waters around Long Island. Sea turtles regularly caught in commercial fishing gear (pound nets) were the loggerhead (Caretta caretta), Kemp’s ridley (Lepidochelys kempii) and the green turtle (Chelonia mydas). These captures were part of a cooperative program with commercial fisherman between 1986 and 1996. Upon capture, straight carapace length, width, and weight were recorded. Each animal was then tagged with either a Monel flipper tag or Passive Integrated Transponder (PIT) tag.
Sea turtles taken in pound net captures in 1996 included 31 original captures and 5 recaptures. The 31 original captures included 7 greens, 12 ridley’s, and 12 loggerheads. The recaptures included 3 greens, 1 ridley and 1 loggerhead. In all years except 1992, the total number of sea turtle captures was greater than the number recovered in 1996. The pound net recovery program was initiated in 1986. Between the years of 1986-1989 the numbers of turtles recovered were influenced to an unknown degree by effort. As a result the numbers of animals recovered during this time is difficult to correlate to the current numbers of recoveries.
In all years until 1996, loggerheads were the dominant species captured. From 1986 to 1995 the number of loggerheads recovered represented from 48% to 78% of total captures. The data revealed a significant decrease of loggerheads for 1996 compared to previous years. The number of loggerheads recovered for 1996 was 12. The decrease of total sea turtles captured in 1996 is largely accounted for by the decrease in the number of loggerheads recovered. In all years except 1990, the total number of loggerheads recovered was greater than either greens or ridley’s. The mean number of loggerheads per year for all years is 19.54 (sd ±10.24) and the twelve loggerheads recovered in 1996 is significantly lower. The decrease in loggerhead and total sea turtles was also observed in the stranding records for New York State during 1996.
Concurrent with the decrease in loggerhead captures was an increase in the percentage of green sea turtles recovered. The percentage of green turtles captured in 1996 was 22%. The mean percentage for all previous years was 17%. With the exception of 1994, the number of green turtles recovered remained relatively stable from 1985 to 1996 with a mean of 6.36 (sd ±5.6) and 7 were recovered in 1996. The seven original captures in 1996 are not significantly different than the mean and again the increase in the percentage of green is related to the decrease in loggerhead recoveries.
Turtle captures in the waters of eastern Long Island have shown similar patterns from 1986 to 1995. In 1996, however, turtles were recovered in western Shinnecock Bay and Peconic Bay. The Peconic Bay recoveries were due to a newly introduced fishing method in the Peconic system known locally as ‘fish pots.’ These pots are very different in design than pound nets since the entire structure is submerged. The structure of these traps would prevent entrapped sea turtles from surfacing to breathe, something a pound net does not do. Although both turtles caught in these “pots” were alive they were likely only recently trapped. This fishery could cause mortality, something we have not seen yet in pound nets for New York.
The decrease in the number of loggerheads observed is not well understood at this time. The 1996 summer was slightly cooler than recent years and it is possible water temperatures effected the distribution of this species to the region. Unfortunately, data on temperatures in earlier years was not available for complete analysis and further examination may elucidate what effect, if any this had. It is also possible that the local pound net fishing effort may have effected the capture of this species. Due to recent New York State regulations regarding take of bluefish (Pomatomus saltatrix). This has been reported by the fisherman to cause them to both shorten their season and reduce the numbers of nets they are fishing. We are presently attempting to quantify this. However, it involves somewhat subjective data since the effort of each individual has not been quantified in previous years and is solely based upon reports of the number of nets set. Although there was a significant increase in the number of cold-stunned sea turtles in 1995 (fig) it is unlikely this has effected the number of loggerheads recovered in 1996. Standard carapace length measurements for all years and 1996 are quite similar (ref)with a very small standard deviation (1986-1995 mean 50.07 sd ±6.44; 1996 mean 49.79 sd ±5.57). This indicates that turtles found here are largely a single year class, and subsequent year classes recoveries would not be effected by the previous years cold-stunning.
It is also possible that some factor outside the New York region has caused a decrease in the number of loggerhead recovered. This could include various populations parameters or changes in Gulf Stream eddies. These were not examined for this study.
Continuation of the monitoring of sea turtle populations in New York will enable a better understanding of the distribution and habitat usage’s of these species. It will also assist in identifying sources of mortalities not seen in other areas. The long term nature of this study is unique for the Northeastern United States and provides important information of sea turtle movements in northern waters that may be part of developmental habitats.