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Full-Text Articles in Environmental Sciences
Long-Term Survival Of Humpback Whales Radio-Tagged In Alaska From 1976 Through 1978, Sally A. Mizroch, Michael F. Tillman, Susan Jurasz, Janice M. Straley, Olga Von Ziegesar, Louis M. Herman, Adam A. Pack, Scott Baker, Jim Darling, Debbie Glockner-Ferrari, Mark Ferrari, Dan R. Salden, Phillip J. Clapham
Long-Term Survival Of Humpback Whales Radio-Tagged In Alaska From 1976 Through 1978, Sally A. Mizroch, Michael F. Tillman, Susan Jurasz, Janice M. Straley, Olga Von Ziegesar, Louis M. Herman, Adam A. Pack, Scott Baker, Jim Darling, Debbie Glockner-Ferrari, Mark Ferrari, Dan R. Salden, Phillip J. Clapham
United States Department of Commerce: Staff Publications
Invasive tags designed to provide information on animal movements through radio or satellite monitoring have tremendous potential for the study of whales and other cetaceans. However, to date there have been no published studies on the survival of tagged animals over periods of years or decades. Researchers from the National Marine Mammal Laboratory and the Woods Hole Oceanographic Institution tracked five humpback whales with implanted radio tags in southeastern Alaska in August 1976 and July 1977, and tracked two humpback whales in Prince William Sound, Alaska, in June 1978. All seven of these individually identified humpback whales were resighted at …
Dramatic Shifts In Hawaiian Monk Seal Distribution Predicted From Divergent Regional Trends, Jason D. Baker, Albert L. Harting, Tracy A. Wurth, Thea C. Johanos
Dramatic Shifts In Hawaiian Monk Seal Distribution Predicted From Divergent Regional Trends, Jason D. Baker, Albert L. Harting, Tracy A. Wurth, Thea C. Johanos
United States Department of Commerce: Staff Publications
Total estimated abundance of Hawaiian monk seals was just 1,161 individuals in 2008 and this number is decreasing. Most monk seals reside in the remote Northwestern Hawaiian Islands (NWHI) where the decline is approximately 4%/yr, whereas relatively fewer seals currently occupy the main Hawaiian Islands (MHI). It is widely accepted that the MHI population is increasing, although there are no formal estimates of total abundance, population growth rate or vital rates. This lack of information has hampered efforts to anticipate future scenarios and plan conservation measures. We present the first estimates of MHI monk seal survival and age-specific reproductive rates. …
A Model Life Table For Bottlenose Dolphins (Tursiops Truncatus) From The Indian River Lagoon System, Florida, U.S.A., Megan K. Stolen, Jay Barlow
A Model Life Table For Bottlenose Dolphins (Tursiops Truncatus) From The Indian River Lagoon System, Florida, U.S.A., Megan K. Stolen, Jay Barlow
United States Department of Commerce: Staff Publications
Data gathered from 220 stranded bottlenose dolphins (Tzmiop tvuncatlls) in the Indian River Lagoon system, Florida, were used to derive a life table. Survivorship curves were fit to the data using Siler’s competing-risk model and a maximum likelihood approach. Population growth was estimated to be between r = 0.0 and 0.046 based on the observed numbers of stranded dolphins. Variance in survival rates was estimated using an individual-based, age-structured population projection model. We estimate that the overall annual mortality rate for this population was 9.8% per year. Sex-specific differences in survivorship were apparent with females outliving males. The …