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University of Nebraska - Lincoln
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Catches Of Humpback And Other Whales From Shore Stations At Moss Landing And Trinidad, California, 1919-1926, Phillip Clapham, Stephen Leatherwood, Isidore Szczepaniak, Robert L. Brownell Jr.
Catches Of Humpback And Other Whales From Shore Stations At Moss Landing And Trinidad, California, 1919-1926, Phillip Clapham, Stephen Leatherwood, Isidore Szczepaniak, Robert L. Brownell Jr.
United States Department of Commerce: Staff Publications
Logbook data from California shore whaling stations at Moss Landing (1919-1922 and 1924) and Trinidad (1920 and 1922-1926) are analyzed. The logs for the two stations record the taking of 2,111 whales, including 1,871 humpbacks, 177 fin whales, 26 sei whales, 3 blue whales, 12 sperm whales, 7 gray whales, 1 right whale, 1 Baird’s beaked whale, and 13 whales of unspecified type (probably humpbacks). Most whales were taken from spring to autumn, but catches were made in all months of some years. The sex ratios of humpback, fin, and sei whales (the three species with sufficient sample sizes to …
Distribution And Abundance Of The Amazon River Dolphin (Inia Geoffrensis) And The Tucuxi (Sotalia Fluviatilis) In The Upper Amazon River, Omar Vidal, Jay Barlow, Luis A. Hurtado, Instituto Tecnológico Y De Estudios Superiores De Monterrey (Itesm), Patricia Cendón, Zully Ojeda
Distribution And Abundance Of The Amazon River Dolphin (Inia Geoffrensis) And The Tucuxi (Sotalia Fluviatilis) In The Upper Amazon River, Omar Vidal, Jay Barlow, Luis A. Hurtado, Instituto Tecnológico Y De Estudios Superiores De Monterrey (Itesm), Patricia Cendón, Zully Ojeda
United States Department of Commerce: Staff Publications
A boat survey was conducted from 5 to 26 June 1993 to estimate the abundance of the Amazon river dolphin (Inia geoffrensis) and the tucuxi (Sotalia fluviatilis) along ca. 120 km of the Amazon River bordering Colombia, Peru, and Brazil. Two survey methods were used: line transects during 5 d and strip transects during 15 d. The line transects were used to estimate the abundance of both species in the main channels of the Amazon at distances greater than 200 m from river banks and islands, and strip transects were used to estimate abundance in the …
A New Birth-Interval Approach To Estimating Demographic Parameters Of Humpback Whales, Jay Barlow, Phillip Clapham
A New Birth-Interval Approach To Estimating Demographic Parameters Of Humpback Whales, Jay Barlow, Phillip Clapham
United States Department of Commerce: Staff Publications
A demographic model is developed based on interbirth intervals and is applied to estimate the population growth rate of humpback whales (Megaptera novaeangliae) in the Gulf of Maine. Fecundity rates in this model are based on the probabilities of giving birth at time t after a previous birth and on the probabilities of giving birth first at age x. Maximum likelihood methods are used to estimate these probabilities using sighting data collected for individually identified whales. Female survival rates are estimated from these same sighting data using a modified Jolly–Seber method. The youngest age at first parturition is …
Behavioral Responses Of Bottlenose Dolphins To Remote Biopsy Sampling And Observations Of Surgical Biopsy Wound Healing, David W. Weller, Victor G. Cockcroft, Bernd Würsig, Spencer K. Lynn, Dagmar Fertl
Behavioral Responses Of Bottlenose Dolphins To Remote Biopsy Sampling And Observations Of Surgical Biopsy Wound Healing, David W. Weller, Victor G. Cockcroft, Bernd Würsig, Spencer K. Lynn, Dagmar Fertl
United States Department of Commerce: Staff Publications
Information on reactions of delphinids to biopsy sampling and healing of associated biopsy wounds is limited. Results presented here report on the behavioral responses of free-ranging bottlenose dolphins (Tursiops truncatus) to remote biopsy sampling procedures, and provide information on stages of surgical biopsy wound repair. Biopsy samples of free-ranging dolphins were collected between February–May 1992 in Galveston Bay, Texas, using a sterilized corer-tipped bolt, launched from a crossbow. A total of 8 direct ‘hits’ were documented, 4 hits (50%) in which a tissue sample was obtained, 2 hits (25%) from which no sample was retrieved, and 2 hits …
First Estimates Of Vaquita Abundance, Jay Barlow, Tim Gerrodette, Greg Silber
First Estimates Of Vaquita Abundance, Jay Barlow, Tim Gerrodette, Greg Silber
United States Department of Commerce: Staff Publications
The abundance of the only population of vaquitas, Gulf of California harbor porpoise (Phocoena sinus), is estimated from four surveys conducted in Mexico between 1986 and 1993, using a variety of methods. A line-transect approach was applied, using some parameters estimated from a related species, the harbor porpoise (Phocoena phocoena). Vaquita abundance is estimated as 503 (CV = 0.63) from 1986-1988 boat surveys, 885 (CV = 0.50) from 1988-- 1989 aerial surveys, 572 (CV = 1.43) from a 1991 aerial survey, and 224 (CV = 0.39) from a 1993 ship survey. A weighted log-linear regression in …