Ecology, Population Structure and Dynamics - 2008 Reports

Abundance, site-fidelity, and habitat utilization patterns of bottlenose dolphins near a National Priority List polluted site and an adjacent reference site in Georgia

Jan 23, 2008 No comments

This project is part of a larger research effort by NOAA to assess the health and contaminant exposure of bottlenose dolphins, an apex predator and sentinel species for ecosystem health, at a National Priority List (NPL) polluted site in Brunswick, Georgia [Turtle/Brunswick River estuary (TBRE)] and a nearby, relatively pristine, reference site [Sapelo Island National [...]

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Validating stranding data in feeding ecology studies of bottlenose dolphins from Sarasota Bay, using long-term observations

Jan 19, 2008 No Comments

We have been using the ratios of stable isotopes in dolphin tissues to examine feeding patterns of bottlenose dolphins along Florida’s west coast. Results from the stable isotope analyses suggest that differences exist at the population level, which allow us to distinguish offshore and various inshore dolphin populations, and we have started to examine potential [...]

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Shark tracking in Sarasota Bay

Jan 19, 2008 No Comments

Part of understanding dolphin behavior is learning how these animals interact with their predators. Large sharks are the only known natural predator of dolphins in the Sarasota Bay area; about 31% of Sarasota’s dolphins bear shark bite scars. Bull, tiger, and dusky sharks are the most likely dolphin predators, based on historic shark stomach content [...]

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Effects of red tide on dolphin prey fish availability

Jan 16, 2008 No Comments

Karenia brevis, the single-celled alga responsible for Florida red tides can affect fishes in several ways. Karenia brevis produces lethal neurotoxins, called brevetoxins, which affect the respiratory system. Fishes can be exposed to the toxins by inhaling them directly from the water through their gills or by consuming food that contains the toxin. Also, the [...]

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Diet determination of Sarasota Bay bottlenose dolphins, using DNA-based identification of prey remains in scat samples

Jan 12, 2008 No Comments

This work is part of larger on-going studies being conducted by the Australian Antarctic Division, developing and applying methods to determine the diet of free ranging cetaceans, non-invasively. We are using the simple concept that if prey is eaten, then prey remains will be present in fecal matter (‘scat’) and the prey can be identified [...]

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Population structure of bottlenose dolphins in and around St. Joseph Bay, Florida

Jan 07, 2008 No Comments

During three Unusual Mortality Events (UMEs), (1999-2000, 2004, and 2005-2006), more than 300 bottlenose dolphins died along the Florida Panhandle. St. Joseph Bay was the geographic focus of the 2004 mortality event. The most recent (1994) NOAA’s Fisheries Service abundance estimate for bottlenose dolphins in St. Joseph Bay is zero, but dolphins are currently observed [...]

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Sarasota Bay dolphin monitoring program

Jan 05, 2008 4 Comments

We have been able to continue our year-round monthly monitoring of the Sarasota dolphin community thanks to support from 15 Earthwatch Institute volunteers and NOAA’s Fisheries Service (NMFS). The Sarasota bottlenose dolphin community is one of the most thoroughly studied free-ranging dolphin populations in the world. We continue to address increasingly refined questions about the [...]

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Investigating impacts of Hurricane Charley and red tide on dolphin abundance, reproductive rates, distribution, and residency in Charlotte Harbor and Pine Island Sound.

Jan 04, 2008 No Comments

Do major ecological disturbances impact resident dolphin populations? The Sarasota Dolphin Research Program was in a unique position to evaluate this question as both Hurricane Charley in August 2004 and a severe red tide in 2005 impacted Charlotte Harbor and Pine Island Sound. These combined events may have affected habitat health, including prey fish availability, [...]

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Comparing patterns of habitat selection at the levels of the population and the individual

Jan 02, 2008 No Comments

Humans tend to think of animal species as being composed of individuals with identical habitat requirements and food preferences. In fact, many foundational theories in behavioral ecology assume that all members of a population behave in the same manner. This is a result of how most wildlife studies are conducted. It is often difficult to [...]

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