It must be spring...

So in finding a new spot for my staghorn fern, I inadvertently made a perfect nesting site for some carolina wrens, who moved in a mere two weeks afterwards.

A week so later, I peeked in and saw some eggs...

Today I noticed a lot of activity going on at the nest, with the birds bringing lots of food in.

Peeking in the nest I saw why... The eggs had hatched.

 

While I watched the pair brought 3 bugs in under 15 minutes.

Carolina wrens like to nest in odd places like mailboxes and broken taillights, and will nest a couple of times a season.  The chicks will fledge in 12-14 days.

Abalone development

I recently got to be a part of an abalone spawning team, where we induced abalones to release their gametes. It was very fun to see the fertilized eggs develop, and interesting for me because it was the first time that I had actually seen spiral cleavage in action! It was so different looking than radial cleavage...

I did not manage to get pictures of all of the stages, as I had to sleep, so expect some gaps. But I hope you enjoy this abalone development slide show that I put together of the stages I did see.

Grunion Development: Day 9

Not much seems to have changed from day 8 to day 9. The grunion is still the same size, and has not gained any new pigmentation. The yolk has decreased a bit, but at this point no major developmental; changes are visible. However, on day 9 they are much easier to hatch!


You can still see the remnants of the yolk in the young fish's stomach.

Grunion Development: Day 8

The eyes are fully pigment, and the body as well. The body has grown to such a length that it wraps around the inside of the egg a little over 2 times. The oil droplets have been completely depleted, and there is a little yolk left. What you can't see is that the embryo is very active, with eye and body twitches being quite common.

Grunion Development: Day 6

The embryo has grown, with the tail wrapping all the way around the egg and back around the head. The eyes have a lot of pigment and the body is starting to get a little pigment. The oil droplets are almost all used up and the yolk has a lot of blood vessels connecting it to the embryo.

Grunion Development: Day 4

The embryos are noticeably larger, and structures are becoming readily apparent. You can see the nerve cord running down the center of the embryo. gill arches forming behind the eye, and the eye itself has an indented pupil.

What you can't tell from the picture is that the heart is also nociable and pumping, and there are musculature visible along the length of the tail.

Grunion Development: Day 3

Now you can clearly see many features of the developing embryo. It has also grown large enough to wrap around the back of the egg, with the tail just peeking out on the left hand side. The oil droplets are being used up and condensed into one large drop right in the center.

Grunion Development: Day 2

Now it's approximately 37 hours after fertilization. You can still see the oil droplets off to the left, but the embryo has under gone some big changes. Instead of being a cap of cells it now has a definite form, with the head and developing eyes in the center, and the rest of the body trailing off to the top right.

Grunion Development: Day 1

I thought I'd take some pictures of grunion eggs as they develop, just because I could. Here is day 1, approximately 13 hours after fertilization. You can see the dark orange oil droplets in the center, and a pale yellow cap of cells off to the left. That is the developing embryo.

You know how I love me some developing squid... Here is some before and after shots of the common market squid.

You can see that baby still in the capsule with the yolk coming out from the tentacles. When the squid is ready to hatch, the capsule and the chorion (which surrounds the embryo) are greatly thinned. However, they still present a considerable barrier. Squids have a hatching gland, called the organ of Hoyle, which produces an enzyme that dissolves the chorion and the capsule wall.


Here's a nice quick shot of a post-hatch baby. You can see some of the chromatophores, pigment-containing cells, as black dots on their body.



To round off this post, I thought I'd close with a video of those chromatophores in action!

Story of a black jelly

Last summer we had a rare event. Tens of black sea nettles (Chrysaora achlyos) washed ashore on our beach. These guys are pretty rare, so we jumped at the chance to get some gonadal tissue to start a new culture of jellies. We collected the adults from the beach, and I extracted the gonadal tissue from the insides of the bell. (This was a rather painful process which involved me getting stung for three days.)

I used bits of the tissue to sex the animals; females had eggs, and males had packets of sperm. After I figured out who was what, I put a little bit of male gonads and female gonads together in a petri dish and mixed them up, to beak open the male's sperm packets. (It felt a bit like making red scrambled eggs.)

Male sperm packets

Female tissue with eggs

After 3 days, planulae were spotted swimming in the petri dishes.


After 5 days, the planulae settled to the bottom to become polyps. These are newly settled with only 2 fully formed tentacles.


Four months later, I am very happy to say that my polyps have begun to strobilate. I have some beautiful ephyrea, that will become (in my opinion) the prettiest-colored jellies ever.

Bringing in the new year

This new year's day has been pretty exciting because for the first time ever, we still have baby California spiny lobsters in our care. This little guy was 184 days old, about 14 days older than last year's record. He was also a little smaller than a quarter, all stretched out.

Larval lobsters can remain in the plankton for up to a year, so we still have a way to go before it settles and looks anything like the lobsters we know. This year, we've seen some growth that we've never seen before, new legs and tail sectioning, and it's mostly due to a difference in the diet we're feeding them.


Here's hoping that they continue to grow in the new year!

More cute worms!

In addition to Owenia there were lots of other larvae in our plankton tows. These are just two of my favorites, although everything looks cute when it's a baby! The top is some sort of polychaete, and the bottom is not technically a worm although it is worm-like.


It is a phoronid, and is most closely related to bryozoans and brachiopods. Their bodies are shaped like worms, although they have a great feathery lophophore which they use to filter water for food, and their anus loops out near their mouth. They also live in tubes, and they can brood their young in it. There are only 20 species of phoronids world wide.

Night lighting

One of the way we get larvae is by lowering a light into the water at night. Many animals are photopositive, that is attracted to the light, which helps them maintain their position in the water column and find food.

By lowering the light at night, we create a sharp gradient of light and can attract a lot of animals. Most of them in this video are megalopae (baby crabs) and epitokes. The epitokes are fast, pinkish, and wiggle as they swim, while the megalopae are much bigger and chunkier.

Friday Harbor

So, I have just gone up to Friday Harbor Laboratories and have been enjoying my immersion in science after quite a long spell without. I am learning all about larval biology, so have been going on field trips to many different sites, like this mudflat pictured above, to look at egg masses and collect larvae.

One of my favorites is this Owenia sp., which is a type of worm that builds tubes out of small sandy particles. This creature has an interesting development, as the juvenile worm develops around the intestine of the larval body. When it is ready to settle, it drops out of the sac where it was developing and eats its old larval body.

Life Photo Meme: Frosted

Kingdom: Animalia

Phylum: Mollusca

Class: Gastropoda

Order: Nudibranchia

Family: Tethydidae

I guess all larval animals have a clear, frosted appearance, but I choose this particular larva because it's special to me. This is a veliger larva, a larval stage which is typical to the marine snails. In particular, this is a baby lion nudibranch, Melibe leonina. This larva hatched today, and I am trying to rear them to adulthood.

The fuzzy bits toward the bottom of the veliger is cilia, which helps it swim. The two round dots that look like eyes are actually statocysts, which help the larva figure out orientation (up and down). These guys have a thin shell in the veliger stage, which they lose when they metamorphose into juveniles.

Adult lion nudibranchs live in the kelp canopy, and eat small creatures that live on the kelp or float by. They use their big oral hood much in the same way a Venus fly trap catches flies. Because of the way they feed, they are one of the easiest sea slugs to keep in a public aquarium. They are also one of the few sea slugs to swim.

From Biological Tales from the Brine Queen

It will take a little over month before these little veligers metamorphose and settle into the adult form. It will be a welcome challenge to try and keep some of them alive for that long.

Life Photo Meme: Narrow

Kingdom: Animalia

Phylum: Mollusca

Class: Cephalopoda

Order: Octopoda

Family: Octopodidae

This little two-spot octopus was only about 2 months old when the picture was taken. He (or she) would be able to fit into VERY narrow spaces, as the only hard part on its body is its beak. An adult two-spot octopus can get up to three feet in length (arm to arm), and has a beak about the size of you pinkie fingernail. This little guy was almost an inch (arm to arm), so I can't even imagine how small its beak is. But I do know that it fit into the most amazingly small spaces to enact its escapes.

This little octo is still going strong at the aquarium, and is about 6 months old at this point. We have had some success in feeding it, even though its diet constantly changes as it grows. Its about 2.5 inches from arm to arm now. Hopefully, we will be able to raise it to adulthood.

Life Photo Meme: Inverts

Kingdom: Animalia

Phylum: Mollusca

Class: Cephalopoda

Order: Teuthida

Family: Loliginidae

The above is a picture of market squid, Loligo opalescens, eggs. The eggs are laid in capsules by the female in clusters on the bottom of shallow sandy areas. Each egg capsule can hold about 300 eggs, and the female can lay 20-30 capsules in a breeding event. Eggs hatch in 3 to 5 weeks, depending on the water temperatures. The hatchlings, called paralarvae, are about 6mm (1/4 in) in length at hatching.

Here is a cropped part of the above picture, so you can better see the little squids developing in their eggs. They didn't have any pigment yet, and were about 4-6 days from hatching.

Uber-cute!

I love walking into my workplace and seeing stuff like this. This baby pacific seahorse is just three days old and about a centimeter long. The male gave birth to a batch of babies after a 9 day gestation period. Normally, they can hold 2-3,000 eggs in their pouch, but this particular daddy gave birth to only 75. That could be because the female dropped the eggs when she was transferring them to the male, or because she just did not make that many eggs. I am looking forward to seeing these little cuties grow up.

BTW, those dots you see around the seahorse are rotifers, which are the current food source for our babies (and only ~0.5mm long!).

Drive by posting

Another super cute baby octopus picture! They seem to be pretty healthy looking, and have the strength/ cunning to escape their enclosures. So far, I've returned two to their tanks after they have escaped to the wet table. One of them even caught its first meal the other day. (We fed it a small grass shrimp) Hopefully, they will survive to adulthood.