CZS Sarasota Dolphin Program

Wednesday, August 8, 2007

August 8, 2007

Yaana is moving widely, between deep within the bay and outside the mouth of the bay.

Tuesday, August 7, 2007

August 7 - Tons of Transmissions!

Yaana continues her movements from the bay into the waters just outside the mouth.

After more than five months and 37,000 transmissions (half again as many as advertised), the transmitter is still indicating good battery strength. Some tracking weirdness over the weekend---we have been getting a larger number of satellite "hits", which may be indicative of Yaana spending more time at the surface, or may reflect really calm conditions; and the final location Saturday put her in the middle of the island! Hopefully this just indicates a bad position that will be resolved with additional CLS data processing... And if not, well, she has been a lot more aquatic since then, as you would expect...

Wednesday, August 1, 2007

August 1, 2007

Yaana is at the mouth of the bay. Yesterday, Pablo's team briefly observed, but was unable to photograph, a tagged dolphin in the region where Yaana has been spending time. The tag looked to be intact and in the expected position on the fin.

Tuesday, July 31, 2007

July 31, 2007

Yaana is moving back and forth in front of the town, from the bay to the mouth. Hopefully this will make it easier for the search crew to find her.

Monday, July 30, 2007

July 30, 2007

Over the weekend Yaana hung out outside the bay. Today she is back inside the bay. We hope this will facilitate the team's search for her, if the weather begins to cooperate.

Science as it Happens!

Ranging Patterns and Habitat Use of Franciscana Dolphins off Argentina: 2008

In March 2008, Chicago Zoological Society conservation scientists Randall Wells, Jason Allen, and Aaron Barleycorn returned to Bahia San Blas, Argentina, to work with Pablo Bordino and his dedicated team of students, colleagues, and fishermen, and a veterinary team from Disney’s Animal Programs, to conduct additional satellite-linked tagging of franciscana dolphins. Building on the tagging and tracking work during 2007 that indicated a high degree of residency to Bahia San Blas over periods as long as six months, the next phase of the project was designed to address specific questions about:

1) what part of the water column the dolphins use – if the dolphins show preference for water of particular depths, then fishermen might be able to set their nets at different depths in order to avoid the dolphins. Up to three satellite-linked transmitters with time-depth recorders (TDRs) will provide information on the depths of dives as well as locations.

2) developing correction factors for aerial and boat surveys for dolphin abundance that take into account the dive patterns of the animals – the TDRs provide information on dive durations and time spent at specific depths where the animals might be visible to scientists.

3) social patterns – deploying tags with identical duty cycles, it is possible to determine if the animals exhibit a stable or fluid pattern of social associations, through examination of their location data to see if they remain together or separate. In addition to the location data from the TDR tags, as many as 5 location-only tags may be deployed. Genetic samples collected during the tagging process will allow determination of relatedness of dolphins caught together.

The first two transmitters, both TDRs, were deployed on a juvenile male (#42483) and an adult female (#42485) on March 4, 2008. As data are received from these and subsequent transmitters, they will be displayed on this site, as maps showing dolphin locations.

The radio transmitter ("tag") was specially designed for dolphins and weighs only 15 grams. The expected battery life is approximately four weeks, and the tag naturally falls off some time later.

Major support for this project was provided by the Chicago Zoological Society and Disney’s Animal Programs, with tags and tag data processing assistance provided by Dolphin Quest.