Monday, July 20, 2009

#135: Why are the seals on the rocks?

If you have walked by the Atlantic Harbor Seal exhibit recently, you may have seen something that only happens during this time of year. Our harbor seals are molting! Molting is a process where a seal sheds its old coat of hair as a brand new beautiful coat grows in. For much of the two to three weeks it takes to molt, our seals spend a lot of time hauled out on the rocks. It may look like they are just taking advantage of the beautiful summer weather, but staying out on the rocks serves a really important purpose.


This gives them the opportunity to rest and conserve energy as their bodies go through the molting process. During the molting season, which begins in early July and ends in early August, there are days when you may find all seven seals taking a snooze during the day. As the new hair grows in, their skin can be more sensitive, so we give the seals Vitamin E until their new coats are complete. Check out the picture above. How many seals can you find hauled out on the rocks?


Trumpet




Amelia


Today I took a few pictures of the seals that are right in the middle of their molts. If you look closely, you can see the color changes, especially on Amelia. The darker patches on her back show off her beautiful, silvery colored new hair. The rest of her body is still covered with her older hair, which has now taken on a yellow tint. The hair even feels different. The old hair has a rough feel to it, while the new hair feels very soft. Stay tuned for some more pictures as they continue to grow in their new coats!

~Patty

subscribe



Labels: , , ,



Tuesday, June 16, 2009

#128: Smoke Rorschach Test

The harbor seals are approaching the molting season when they will all get new coats of hair. At this time of year, many of the seals start to get a small accumulation of algae growing on their old coats. Our oldest seal Smoke tends to move a little slower than the other seals that live at the Aquarium, and it seems like algae tends to stick to her a bit more ... especially on her head.


To me the algae on her head looks like a bird. What do you think it looks like?



In July Smoke will molt and look good as new. Click here to see what Smoke looked like last year mid-molt. Here's what she looked like when she finished her molt last August. What a difference!


-Justin

subscribe



Labels: , , , ,



Friday, May 29, 2009

#117: Video of a White Lobster Molting

As you know, we have been doing a lot of work with lobsters the last few months. Justin even posted a video of one of his lobsters molting. Just this week, Anita taped another lobster molting, but you'll notice this lobster is a surprising color.




The lobster in this video is one of hundreds being raised at the Aquarium's Lobster Research and Rearing Facility. Anita, manager of the lab, happened to stumble upon this lobster halfway through molting. The first thing you might notice is that the lobster is white. This lobster was not born this way, but rather it has been eating a diet that lacks the pigment astaxanthin. Astaxanthin provides a lobster with its shell color, so if a lobster doesn't eat astaxanthin, they will turn white! For more information on lobster shell color and research, visit the Lobster Lab's web page.



The old shell is a light blue color, and the lobster itself is white. At the start of the video, the lobster is trying to get its claws, abdomen and tail out of the old shell. The lobster definitely looks like it is having a difficult time. Although the molting process only takes a few minutes, a lobster spends much of its life preparing to molt or recovering from molting. After molting, the lobster will bring water into its tissues and increase in size – sometimes it will gain up to 50% of its previous weight. The new shell hardens over the next couple days and the lobster will eat its old shell for nutrition.

Thanks Anita for the great video!

subscribe




Labels: , , , , ,



Friday, April 3, 2009

#102: Who's Who?

One of the most popular questions the trainers hear is "How do you tell the harbor seals apart?" The answer sounds simple; just by looking at them, but it can take a long time if you don't see the seals every day.

First you need to know who is in the exhibit. We currently have seven Atlantic harbor seals in the plaza exhibit--two males and five females. We can divide them into two easily identifiable groups, the 'spotted' and the 'non-spotted' seals. The spotted seals have distinct dark spots on their necks and bellies. All of the 'spotted' seals are related.

Our spotted seals are Trumpet Cayenne & Chacoda:

Link

The non-spotted family: Amelia, Reggae, and Smoke:

Look at the picture below of the non-spotted family. Can you tell who is who? How did you tell?



Last but not least, our seventh seal is Lana. She is not related to any of the other seals, but she most resembles the non-spotted family.



Other than the obvious spot patterns, we look for differences in the shape of the head, nose, and eyes. They also differ in their body length and girth, but this can be deceiving. The seals' weight can fluctuate between 10 and 30 pounds depending on the time of year, so weight isn't a reliable way to distinguish individuals.

Now that you've looked at the pictures, will you be able to tell the seals apart on your next trip to the Aquarium? Don't worry if you can't. Start by telling the spotted from the non-spotted first. It took all of us a while to figure out Who's Who too and we see them every day!

subscribe



Labels: , , , , , , , , ,



Monday, March 2, 2009

#98: Lobster Growth Spurt- Night Vision Video!

This is cartoon from the "Maine Dictionary."
A sheddah is a lobster that recently molted.

A few weeks ago I told you that we were starting to train some juvenile lobsters in the Aquarium's lobster research lab. These lobsters were hatched at the Aquarium and it's been really interesting watching them grow. Lobsters don't grow gradually like we do, they only grow when they molt their shells. Their shells don't grow with their body, so in order to get larger they have to pull their bodies out of the old shell. They have a new shell underneath but it is very soft.

While they are soft they take water into their bodies to expand, and then harden up after that. All crustaceans molt. Have you ever eaten a soft-shelled crab? You're eating a crab that has recently gone through this molting process. Younger lobsters tend to molt more frequently than older ones. I think the coolest things about lobster molting is that they usually eat their old shell after they've shed it. Yum!




The other day Erin and I went up to do a training session with the lobsters and we caught one of my lobsters in the middle of molting. This video shows you the end of the molting process. We took it with "night vision" which is why the lobster is green with creepy glowing eyes. He is just about all the way out of his old shell.







With some encouragement and lamaze breathing techniques from Erin and me, it was quickly all the way out and well on its way to getting bigger. You can see its old shell in the lower right side of the screen. My little crustacean's growing up so fast.

-Justin

subscribe




Labels: , , ,



Tuesday, August 12, 2008

#34: Molting Update

The molting season is in full swing for the harbor seals. Here are some photos from the past few days of Smoke, our oldest harbor seal.





The brown areas are patches of old hair, the silver is all new stuff.


-Justin

subscribe



Labels: , , , ,



Thursday, July 24, 2008

#32: Molting

The air is warm, the sun is bright and the faint (and sometimes not so faint) aroma of sunbathing harbor seals fills the air. Summer is molting season. The harbor seals will lose their hair soon. No need for Rogaine or Propecia, though. Our seals will replace their lost hair on their own over a couple of weeks. Since the seals rely on their hair to protect their skin they need it to be in good condition, so their coat is replaced once a year. During this time they tend to spend more time out of the water. We call this "hauling out." Sunbathing promotes more blood flow to the skin and allows for a quick replacement of healthy hair. While they are molting their appetite decreases and they often aren't their usual spunky selves. Growing all new hair is hard work! By the end of August all of our harbor seals will have new glossy coats appropriate for any herbal shampoo commercial.

-Justin

subscribe



Labels: , , , ,