Enigmatic Egg Masses

Wednesday was great because we got to go to TWO field sites in one day! Going into the field is by far my favorite part of marine ecology. We wanted to collect two more species of snails: Crucibullum spinosum and Bostrycapulus calyptraeformis. Here I am in the top photo and Allan in the bottom photo. We went to Chumical in Veracruz, but we didn't find anything! Maybe the snails live in patches and we just didn't look in the right spots.

Me (Gina) at Chumical at low tide.

Allan looking for C. spinosum and B. calyptraeformis at Chumical at low tide.

Recently, we have been learning about the moon snail (family Naticidae, genus Polinices) egg masses and I want to try to describe the egg masses as best as I can to try to help us determine the species we have been observing. We don't know what species it is, and we would especially want to know if we are looking at multiple species! I took some vertical trans-sections of two egg masses we found at Venado Beach on Feb 11 and also of two egg masses from Chumical on Feb 13. Between the sand grains, I was looking for egg capsules. Here's what I saw:

Moon snail  (Polinices sp.) egg mass from Feb 11, 2013, 

collected at low tide in the middle of the day. 

I think those round, shiny spherical things are the larvae. I teased the egg mass apart to get a better idea. See the next photo:

After I teased the egg mass apart, this is what I found (above). I'm pretty sure those are moon snail larvae. They look like the hatchlings we have taken pictures of after rearing the eggs in the lab. See the next photo:

Moon snail hatchlings, reared in the lab. We keep the egg masses in cups until 

they erode and larvae are released, then we preserve them for photography.

 I also looked more closely at two egg masses I collected from Chumical on Feb 13. The shape of the egg mass was a bit different than those from Venado Beach, so I thought maybe it was a different species. Below are the ones from Chumical. They seem to have a shorter central margin. I don't have pictures of the Venado Beach egg masses, but I'll try to take some soon to compare!

Egg mass #1 from Chumical, collected on Feb 13 at low tide during the afternoon.

Egg mass #2 collected at the same place and time as #1.

Here's the vertical trans-section:

I couldn't identify any egg capsules or hatchlings in these, even when I teased them apart. I'm thinking that it probably depends a lot on how old the egg mass is: older ones will have more developed larvae. So maybe this one is younger? But then where are the egg capsules with the developing embryos? I still have much to learn!

Enjoying SICB

In 2012 and 2013 CollinLab interns presented posters at SICB.  Posing for the boss's photos wasn't so much fun, but other events made up for it.

Allan Carrillo, San Francisco, CA.  2013

Matt Starr, San Francisco, CA.  2013

Caitlin Shishido, Charleston, SC.  2012

Jeanette Hofstee, Charleston, SC.  2012

Isla Barro Colorado

By Gina Contolini

    Today I went to Barro Colorado Island!

 It is an island in the man-made Gatun Lake in the Panama Canal and is STRI's primary site to study tropical lowland forests. It has a TON of diversity. There is a large, long-term ecological survey taking place were every tree larger than 1 cm in diameter in a 50 hectare plot was tagged and measured and is being monitored for many years. I went with my friend Mallory and her roommate Marjorie who works on the island studying tree fungus. With our pants tucked into our socks for protection against the biting bugs like chiggers, we trekked through the dense flora on trails made of cinder blocks and saw plants with spikes, spines, ants, vines, and REALLY big trunks. We also saw quite a few howler monkeys!

Definitely watch this video put out by the Smithsonian: 

Barro Colorado Island: BCI - Official Video 

 - Smithsonian Tropical Research Institute

Here are some of my favorite pictures!

We arrived as the sun was rising over the canal.

This is the boat you have to take to get to BCI. There was 

only one in the morning to get there and one in the afternoon

 to come back, so if we missed it, we would have been stuck!

Here is the view of the labs as the boat arrives at the dock.

This plant is really cool!

Some cool fungus!

Tarzan!

A striking picture of a tree.

Mallory and me climbing the tree!

I followed a butterfly around until it stayed still enough for a picture!

Howler monkeys. This one has a baby with it.

The view of the canal or lake from the lab campus.

It was really fun and I plan to go back because STRI gives free rides (about 45 min) to their interns every Thursday. You need to sign up about a week in advance, and buffet-style lunch is provided for about $4. It was really good, too--rice, beans, fried fish, steamed vegetables, plátanos al tencación, which are heavily fried pieces of plantain; lettuce, tomato, cucumber, and cake for dessert. Since the communication is very limited on the island, we couldn't go out on the trails without someone who worked there, which was a little disappointing because we wanted to explore. But overall it was very fun and well worth waking up at 5 am on a Sunday! I hope to see much, much more of Panama before I die, and I don't mean just on my current internship!