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I always find that autumn is a tough season for me, in terms of maintaining enthusiasm and fascination with the world around me. I feel, like most creatures, that autumn is a time to hunker down and take it easy until the winter solstice, after which we'll be gaining daylight again instead of losing it. Even if we get blasted by El Niño storms in January and February, it will be easier for me to feel energized simply because the days will be getting longer.

However, even though I really want to hole up with books, tea, and knitting (hi, Junkies!) life goes on and I can't ignore the siren call of the natural world. This morning I went whale watching with some of my students. It was a class trip organized by the other instructor for the course, and almost all of my students came along. If you know me, you probably know that I have a history of horrendous seasickness. As in so awful that none of the OTC meds even touch it, and although I have tried some of the prescription meds they all make me so drowsy that I can't drive or even really stay awake.

It has been a good year for whale watching in Monterey Bay. Humpbacks have been everywhere the past several weeks, showing off all their acrobatic skills and lunge-feeding right off the beaches in Santa Cruz. So it really is a fantastic time to go whale watching, and since I had to go with my class I asked my doctor about other seasickness drugs to try. She gave me something that has worked for other people, including the pharmacist who filled my prescription, and although I've been burned before by the words, "Oh, this will work. You'll be fine!" hope springs eternal and I tried it. And by George, I think it worked! Not that the seas were bad at all, but I think that if I'd gone drug-free I would have been substantially less happy out there.

We did see whales, but for the most part they were pretty far away. They didn't spend much time at all on the surface, just a breath or two and then a show of the flukes as they dove to deeper water. The only breaches we saw were way off in the distance. There were a lot of common murres swimming around, which were extremely fun to watch. They are ecologically similar to penguins in the southern hemisphere and even resemble penguins, with their "tuxedo" plumage.

I was trying to photograph some murres on the surface when this happened:

Pair of common murres (Uria aalge) and a humpback whale (Megaptera novaenagliae) on Monterey Bay 16 October 2015 © Allison J. Gong
Pair of common murres (Uria aalge) and a humpback whale (Megaptera novaenagliae) on Monterey Bay
16 October 2015
© Allison J. Gong

Most of the murres scattered when the whale surfaced, and I was lucky to get even two of them in the frame.

We also saw a lot of pelicans.

Adult (white-headed) and juvenile brown pelicans (Pelecanus occidentalis) in Moss Landing Harbor 16 October 2015 © Allison J. Gong
Adult (white-headed) and juvenile brown pelicans (Pelecanus occidentalis) in Moss Landing Harbor
16 October 2015
© Allison J. Gong

Those browning lumpy things in the water at the top left of the photo? Those are sea otters.

And look at this!

Assorted wildlife covering a dock in Moss Landing Harbor 16 October 2015 © Allison J. Gong
Assorted wildlife covering a dock in Moss Landing Harbor
16 October 2015
© Allison J. Gong

The rocks in the background are covered with adult pelicans. The upper dock is occupied by Brandt's cormorants (Phalacrocorax penicillatus), which appear to require more personal space than do pelicans, and one of what I think is a great egret (Ardea alba). The lower dock is almost submerged by California sea lions (Zalophus californianus).

I'm counting today as a minor victory, and I'm grateful to have been able to enjoy it. This is the first time I've been out that far on Monterey and not wanted to die. 'Tis the season for gratitude, isn't it?

ORGANISM OF THE MONTH: Pugettia producta, the kelp crab

For a few months now, I've had a pet kelp crab running around in one of my seawater tables. I don't remember where I collected it, or even whether or not I collected it at all; quite often crabs and other animals arrive as hitch-hikers on kelp that we bring into the lab to feed urchins, and I end up with many cool critters in my care that way. However she got here, this crab has been rather a pain in the butt during her stay with me. For at least a couple of weeks she got stuck in the drain of the table and would not come out despite three experienced marine biologists (including yours truly) trying to persuade her by altering water flow and offering food bribes. Then she disappeared from the table drain and I assumed that she had gone all the way through to the floor drain, where she could live quite happily for all eternity. Then she suddenly showed up again in one of my urchin baskets. When she came back up from the drain and how long she'd been hiding, I'll never know.

Wondering why I keep referring to this crab as "she"? It's because I know for certain that she's a female. Here's the secret to how you can determine the sex of brachyuran crabs (most of the common crabs: kelp crabs, shore crabs, rock crabs, even Dungeness crabs): You look at the shape of the abdomen, which is curved forward on the underside of the body. See here:

Abdomen of female Pugettia producta. 16 October 2015. © Allison J. Gong
Abdomen of female kelp crab (Pugettia producta)
16 October 2015
© Allison J. Gong

The abdomen is the broad flat upside-down-U-shaped panel that covers about half the width of the ventral surface. Female crabs brood their embryos under the abdomen, hence the broad shape. Male crabs of the same species have a much narrower, pointed abdomen.

Since her escapade with the drain the crab has been more, shall we say, co-operative. She's still free to scurry around at will in the table, but I haven't found her doing anything objectionable such as tormenting urchins or trying to get down the drain again. She has also been eating well.

Until this past week, that is. On Monday she accepted a piece of food but then abandoned it without even tasting it. On Wednesday she fled from the food, which I took to mean that she was getting ready to molt. Like all arthropods, crustaceans molt their exoskeletons every so often. The decapod crustaceans I'm most familiar with tend to off their feed for a few days before molting, and usually the actual shedding of the exoskeleton occurs at night. Then we show up the next day and voilà! like magic there's a new, bigger crab in the table.

Ms. Kelp Crab stopped eating on Monday of this week. Today (Friday) I didn't get to the lab until about noon, and one thing I noticed in the table was an empty carapace. Sure enough, she had molted. It took a little hunting to find the crab herself, but she wasn't really hiding and her new exoskeleton had already hardened. I'm pretty sure she'll eat on Monday.

Kelp crab (Pugettia producta) and carapace of its molted exoskeleton. 16 October 2015 © Allison J. Gong
Kelp crab (Pugettia producta) and carapace of her molted exoskeleton
16 October 2015
© Allison J. Gong

Living in a rigid exoskeleton means that a crustacean can increase in body size only in the time period between when an old exoskeleton is shed and the new one hardens up. I'm always curious about exactly how much crabs grow when they molt. So today I measured the crab and her old carapace at the same place, halfway between the two points on the lateral edges of the carapace. Huzzah for empirical data! The old carapace measured 27.6mm across, and the new one 33.8mm, for an increase in width of 6.2mm or 22.5%. Mind you, this is simply the increase in one linear dimension of the crab's body. To obtain a more accurate measurement of body size increase, I'd have to have weighed the crab immediately before her molt and after it. Still, it does give an estimation of how much bigger a body part can get when a crab molts.

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