CZS Sarasota Dolphin Program: 6/29/08

Thursday, July 3, 2008

Franciscana Dolphins - Tracking Day #122

Kona remains near Punta Rasa.

Wednesday, July 2, 2008

Franciscana Dolphins - Tracking Day #121

Kona remains south of Bahia San Blas, moving between Punta Rasa and Punta Rubia, near the 20 m contour.

Tuesday, July 1, 2008

Franciscana Dolphins - Tracking Day #120

Four months into the tracking, Kona is heading back toward Bahia San Blas, moving along the 20 m contour.

Monday, June 30, 2008

Franciscana Dolphins - Tracking Day #119

Kona remains south of Bahia San Blas. Relaxing the location quality criteria, we can see that Tunken was near the mouth of Bahia San Blas yesterday, but no more recent data are available.

Franciscana Dolphins - Tracking Day #118

Signal Fading After 45,000 Transmissions
Tunken is still transmitting, but after 45,000 transmissions (only 25,000 were expected for this transmitter), battery strength has declined to the point where the signals are not sufficiently strong to provide good locations (hence, no updated location on today's map) or dive data, and we expect to lose contact with him soon. Kona has made 30,000 transmissions, and is beginning to show some decline in battery strength. She remains to the south of Bahia San Blas.

Franciscana Dolphins - Tracking Day #117

Kona remains to the south of the bay, while Tunken remains in the vicinity of Bahia San Blas.

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.

CZS Sarasota Dolphin Program