Tropicbird Research

Statia is home to one of the largest nesting colonies of Red-billed Tropicbirds in the Caribbean. These birds typically nest in cliffs and rocky hillsides, where they lay a single egg and raise a single chick. As is the case with many native birds that nest on the ground, introduced predators like rats and cats pose a huge threat to successful nesting. In order to understand the rates of nesting success on Statia, the STENAPA team has been monitoring approximately 100 nests on a weekly basis, using motion activated cameras to keep track of activity in nests with eggs between visits.

With their long, streaming tails, these birds are incredibly beautiful. It is a real treat to watch them as they come to and from their nests. A few Magnificent Frigatebirds were patrolling the area, attacking returning birds in order to steal the food they were bringing back to their chicks. Although the frigates are incredibly fast, often the tropicbirds were able to get away.

A tropicbird incubating its egg.

A tropicbird incubating its egg.

Tropicbird removed from its nest for identification and measurement.

Tropicbird removed from its nest for identification and measurement.

The adult Red-billed Tropicbird.

The adult Red-billed Tropicbird.

Measuring the bill and head length of an adult bird.

Measuring the bill and head length of an adult bird.

This juvenile does not yet have a red bill.

This juvenile does not yet have a red bill.

A Magnificent Frigatebird forces a tropicbird to regurgitate a fish it was bringing to its chick.

A Magnificent Frigatebird forces a tropicbird to regurgitate a fish it was bringing to its chick.

A Red-billed Tropicbird approaches its nest.

A Red-billed Tropicbird approaches its nest.

Two Faces

Caterpillars have faces, but not all caterpillars have faces on their butts. On our way up the Quill, we spotted these caterpillars, which seem to be some kind of sphinx moth. Their shape is odd to begin with, but gets even stranger when they adopt a defensive pose.

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I’m not 100% sure that their butt is supposed to look like a face, but I think it is. I am about 0% sure what the face is supposed to look like. Perhaps they evolved to mimic some strange alien creature that has since gone extinct. If you have ideas about what it is trying to look like, let us know.

Here’s one of the photos flipped upside down, in case that helps:

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Hummer Home

I stopped by an Antillean Crested Hummingbird nest I spotted on my first night here to get a look at mom and her chicks. Male hummingbirds are deadbeat dads, so I didn’t expect or see him there. The nest is about the size of a walnut shell. The chicks grow quickly, I believe it’s only about a couple weeks from hatching to leaving the nest.

The mom was gone when I arrived, but buzzed over after a couple minutes. She stayed in the area, but didn’t return to the nest while I was there, so I only stayed a few minutes before going on my way. With her tongue stuck out at me and feathers raised on the top of her head, it seemed like that’s what she wanted, too.

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In The Field: Zeelandia Beach

On my first afternoon on Statia, Hannah and I spent some time on the beach at Zeelandia. The small cliff along the beach was very intriguing, with a layer of white pumice pebbles half a meter thick. Although we were ostensibly scouting for seabirds and any shorebirds that might be on the beach, we quickly turned to smaller creatures.

Like eastern-facing beaches on St. Martin and elsewhere in the Caribbean right now, Zeelandia beach is besieged by sargassum, the free-floating seaweed that the Sargasso Sea is named after. It seems that changing currents have brought these algae from their normal North Atlantic home in several recent years. Although unsightly and often smelly as it decomposes, the sargassum provides food for booming populations of amphipods.

Zeelandia beach with mysterious cliffs and sargassum.

Zeelandia beach with mysterious cliffs and sargassum.

In shallow depressions on the beach full of sea water, the amphipods were swimming and then emerging onto land amongst the algae. Their transition from graceful swimming to slightly awkward hopping and crawling on land made it feel like I was watching early life emerge from the ocean to finally colonize the land.

Amphipods emerge on land like it's the first time.

Amphipods emerge on land like it’s the first time.

The soft, almost muddy cliff face at the edge of the beach turned out to be the home to many spiders and other arachnids. There were one or two species of large wolf spider, a couple species or color variations of jumping spider, an orb weaver and a few other small spider species. Some type of predatory mite was spearing tiny invertebrates, and we found giant pseudoscorpions ten times the size of any I had seen before (but still less than a centimeter long). It felt very much like exploring a cave, albeit a cave with just one wall.

Spider on the beach.

Spider on the beach.

Spi-i-der eyes are watching you, they see your every move.

Spi-i-der eyes are watching you, they see your every move.

Beach cliff jumping spider.

Beach cliff jumping spider.

A wolf spider climbing another spider's web during the day, because why not?

A wolf spider climbing another spider’s web during the day, because why not?

Mite versus amphipod.

Mite versus amphipod.

Giant pseudoscorpion!

Giant pseudoscorpion!

We found mystery burrows with silk and sand doors, cliff-side ant nests and a few other natural mysteries. There were, of course, some Red-Billed Tropicbirds incubating eggs in nests on the cliff face and we even saw an Osprey momentarily as well.

A Red-billed Tropicbird incubating its nest.

A Red-billed Tropicbird incubating its nest.