Friday, June 27, 2008

Franciscana Dolphins - Tracking Day #116

Kona continues to the south, farther than she has been tracked previously, while Tunken remains near Bahia San Blas.

Thursday, June 26, 2008

Franciscana Dolphins - Tracking Day #115

Genetic Analyses: New Hypothesis About Franciscana Mating Associations
Kona has continued moving to the south, while Tunken remains at the mouth of the bay. Martin Mendez has performed genetic analyses on the dolphins captured and tagged this year, and determined that the two males (Tunken and Nahuel) are not related to the females (Kure and Kona, respectively) with whom they were caught and subsequently interacted repeatedly, or for an extended period of time. The hypothesis that they were mothers with their older male calves can now be rejected, leaving in place the even-more-interesting alternative hypothesis that the adult females were spending extensive periods of time with young adult males (based on length), probably for mating purposes.

Extended associations between an adult female and a single, unrelated adult male are quite unusual among the odontocete cetaceans. If extended mating associations are the norm for Franciscana reproduction, then it raises new questions about the impacts of losses of a pair member from fishing nets.

Wednesday, June 25, 2008

Franciscana Dolphins - Tracking Day #114

Kona has moved to the south, while Tunken remains in the bay.

Franciscana Dolphins - Tracking Day #113

Kona remains outside the mouth of the bay while Tunken is inside,

Monday, June 23, 2008

Franciscana Dolphins - Tracking Day #112

Tunken has moved deep into Bahia San Blas while Kona remains outside the mouth.

Franciscana Dolphins - Tracking Days #110-111

Kona remains offshore while Tunken is using the main, deep channel off San Blas.