Submitted by Anonymous on Fri, 11/09/2012 - 09:03
Forums
Weddell Seals in the Ross Sea

Hi Alex

I'm Patrícia from the professional development course. I have a question, about new fur coat.

Do you know how long does the growing an enterily new fur coat? In the case of mothers who first have to nursing ther pups, they have enough time and energy to change the fur? Thank's

Mon, 11/12/2012 - 12:16

Alex Eilers

Hi Patricia!
I decided to ask the experts on this one. The following answer was provided by Linnea - one of Dr. Burn's GA's.
We aren't sure exactly how long it takes to grow the new hair, but its a few weeks at least, and some people have suggested (in other species at least) it takes a few months for the fur to be completely regrown. As for using the fur for stable isotopes for diet - the fur will give you the diet over the time that the fur is grown (so diet over a few weeks). Isotopes are only incorporated while the protein is being deposited (fur is being grown), because the hair doesn't continuously grow (different from people). So no matter when you catch and get your fur sample, you know you have diet information for the period during the molt.
It does take a lot of energy for both nursing their pup and molting, and as you said, they separate those two expensive processes. One thing we noticed over the course of this project, is that while we were deploying tags in January, none of the animals we handled had pupped that year. All the animals that had pupped that year, hadn't molted yet. We aren't sure why this is, and in fact - looking at interactions between reproduction and molt is Jenn's next project.
Hope this helps!
Best - Alex