August 31st, 2011 by Marc AuMarc

Lately it seems like there is always another tropical storm just over the horizon, threatening us with death and destruction. Setting aside for a moment the impact on people and property, let’s consider the impact on wildlife on the island.

It’s been over fifteen years since the last major hurricane hit St. Martin, and according to many folks who have been around here since then there is a lot more wildlife on the island now. The bananaquit (Coereba flaveola, also known as the sugarbird or sucrière), which is extremely common on the island today, was rarely seen in the years after Hurricane Luis. Surely the same is true for many other species that are not as noticeable or well-known.

Even though hurricanes are a natural phenomenon that has impacted the Lesser Antilles since long before the arrival of people, habitat destruction has increased their impact on wildlife. Species that may already be struggling to survive in limited, degraded habitats may by wiped out entirely by a hurricane or take much more time to recover. Differing rates of recovery between species could alter the balance of our island’s ecosystem either temporarily or permanently.

A major hurricane is, in some ways, a big biological experiment. It has the potential to reveal a lot about how island ecosystems are impacted by a natural disaster and how they recover. Of course, much of what we could potentially learn is limited by what we already know about the island in its pre-hurricane state. In many ways, we don’t know that much. For example, there are several species of dove (zenaida, Eurasian collared and white-winged) that are similar in size and preferred habitat and probably compete with each other. If we don’t have a good idea of their relative populations today, we won’t really be able to tell if that changes after a hurricane.

On the other hand, even without a great deal of systematically-collected data, we would probably learn more about the impact of a major hurricane than we did last time around. In addition to data collected by the Réserve Naturelle, the Nature Foundation and groups like Environmental Protection in the Caribbean, there are plenty of less formal sources of data. Digital photography and online photo sharing, for example, will give us a much clearer visual picture of the impact of a hurricane next time around. With more dive centers on the island, there are more people familiar with the local marine environment than ever before. Hiking clubs, like St. Martin Trails, not only increase the number of people with firsthand knowledge of the island, but also make it easier to contact those people to collect personal observations.

Overall, the next big hurricane will be something of a missed opportunity to seriously study the biological impact of such a disaster. On the other hand, we’ll surely learn a lot more than we have in the past, so at least that’s a start.

August 31st, 2011 by Marc AuMarc

I’d love to know more about the history of Terres Basses, the lowlands area to the west of the Simpson Bay Lagoon. From what I can gather, it was mostly uninhabited and unused until the mid-1950s, when most of it was bought by an investor from the US Virgin Islands. One gentleman I spoke with recalled the area from his childhood, when his father was helping to build some of the first villas in the area. He mentioned that there used to be a sand road through the area that was at times entirely covered with red crabs. Apparently workers from Guadeloupe who had come up to do construction were amazed that St. Martiners didn’t eat the crabs.

Because the area is relatively flat and dry, it was probably of little agricultural value, leaving little incentive to make the area accessible. Apparently the first real road was built privately, starting in 1963, turned over to the government in 1968 and only paved in 1975. As fascinating as it would be to know the history of the area before the first tourist development, perhaps there wasn’t much history there to speak of.

Below are a few photos of animals seen on a recent visit to Terres Basses. Because the area is somewhat separated from the rest of Saint Martin, it could potentially host some species that are not found, or rarely found, on the rest of the island. The spider with the green abdomen (probably some kind of Eustala), for example, I have seen only in that area. It was also interesting to find two tetrio sphinx caterpillars that were not on frangipani plants, which is their normal larval host.

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August 29th, 2011 by Marc AuMarc

How many types of spider do you think you can find on St. Martin? If you’ve never been out trying to find them, which probably includes most of the people here, it might be normal to guess ten or twenty species. A quick look through my photos from the last couple years tells me I’ve seen over 50 species, and even that is probably just a fraction of the total. A list of of known spiders from the US Virgin Islands includes about 200 species, which is probably closer to the total here on St. Martin.

Even with decent photos of the spiders, though, it can be surprisingly hard to figure out what species they are. There are about 40,000 known species of spider in the world, and perhaps at least that many that haven’t been described yet. In this day and age, one would think that a photo of almost every species would be available on the internet, but that’s far from true. On St. Martin, it’s entirely possible that there are unknown species waiting to be discovered.

Below are some photos taken in one small spot near my apartment in Grand Case, including six species of spider from five different families. Hopefully someday we’ll know much more about the spiders of St. Martin. Even today, anyone with a camera and some curiosity can help improve our knowledge of local spider diversity.

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August 28th, 2011 by Marc AuMarc

If you want to see a wide variety of birds on St. Martin, a trip to Le Galion and the nearby Salines d’Orient may be your best choice. It may not be more diverse than other wetland areas on the island, but it has many areas where you can approach the pond and get clear views of the birds that are foraging there. On my most recent visit, I had gone to survey for sea turtle nests and only spent a few minutes near the pond, but still saw more than a dozen birds, including a couple species that I hadn’t photographed before.

As a side note, I’ll be uploading some of my sightings to the Saint Martin page at Observado is a site where you can post any sightings of animals (and even plants and fungi) and upload photos if you have them. It is mostly used by birders, and it’s a great resource to see what birds are on the island, where they are found and what time of year they are seen. It even allows users to specify things like whether the birds are mature, immature, in breeding plumage, etc. Even if you’re not certain what you’ve seen, you can upload a sighting and have it identified by a local expert. Definitely check it out and add some sightings. The more data that is available there, the better picture we have of the local wildlife.

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August 26th, 2011 by Marc AuMarc

How often do you see a stick insect on St. Martin? As far as I can tell, it’s pretty easy to go months or even years on the island without ever seeing one. It may be surprising to know that they’re actually quite common, as far as I can tell. For starters, you need to go out at night with a flashlight and look in trees and bushes. You also need to be patient and look really carefully. They’re so well camouflaged, it can be hard to spot them even when you’re looking right at one. Once you find one, though, it gets a lot easier to spot them and there are often several on the same tree.

On St. Martin, they seem to be a species from the Clonistria genus, and they are sexually dimorphic. In this case, the males are brown and the females are green. The size varies a lot depending on their age, and I’ve seen them anywhere from one inch to four or five inches long.

While you’re out looking for walking sticks, be careful. Prowling spiders (Miturgidae) are out prowling those same tree branches at night, as are giant centipedes. Last night I was a little surprised to see a giant centipede eating a snail. Why have such powerful venom if you’re just going to eat a snail? I suppose I was on the French side, though.

Other sightings included plenty of sleeping lizards, a couple brown widow spiders and millipedes mating. If you aren’t spooked about wandering in the dark, it’s really a great chance to get to know some of the island residents that you might not be familiar with.

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August 26th, 2011 by Marc AuMarc

A friend came over the other day after working on some construction, and suddenly this baby centipede was on our balcony. Probably it was hiding in his clothing, which isn’t really a place where you want to have a centipede. Although a bite from this centipede wouldn’t be fatal or cause permanent damage, it can still be very painful.

As far as I can tell, it was a juvenile from a genus of giant scorpions, possibly the species Scolopendra subspinipes, which is found in many tropical areas of the world and is not native to St. Martin. There are a few other related species on the island. They can live for several years and are primarily nocturnal hunters, eating insects, spiders, lizards and other small animals.

What may be most surprising – particularly for those who fear or hate the giant centipede for its bite – is how pretty the juvenile is, as you can see below.

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August 25th, 2011 by Marc AuMarc

When the rains come to St. Martin, overflow channels are opened up from the various ponds. In Grand Case, a fishing village back in the day, this turns into open season on tarpon and other fish that take the opportunity to head out to sea or into the airport pond. Below are a few shots of some folks who dug a channel through some accumulated sand and were fishing with a cast net. Most of the fish caught were tarpon, although there were a couple smaller species. Attracting some tourists, they encouraged folks to take photos while holding some of the fish.

In some ways, it was hard to know what to think. On the one hand, it was nice to see a traditional fishing practice that was probably about the same decades ago. Catching a few fish while it is seasonally opportune seems like a classic example of a sustainable practice. On the other hand, seeing and smelling the pollution in the water made me wonder about the practicality and safety of fishing this way today. This isn’t water I would even want to stand in.

Once again, it’s hard to spend a day on this island without thinking about development and the problems it has caused. Development can be positive, for sure, and there’s no going back to the salt picking days. However, when it isn’t done responsibly, you end up with a pond full of sewage. Much ill to the island has been justified in the name of jobs, but I think this is often misleading.

In reality, the state of the local environment and the well-being of everyday St. Martiners are highly linked. A clean island contributes to the health and quality of life of residents, while problems caused by pollution and environmental degradation disproportionately affect the poor and working class. The cost of responsible development is not necessarily a loss of jobs as much as decreased profits for investors. After all, implementing proper sewage systems and other environmental programs requires labor, and the destruction of the island reduces its value as a tourist destination. It’s impossible to turn back the clock on development, and I don’t think many people living here would choose to go back to the St. Martin of 50 or 100 years ago. I think it is possible to hope for a future where sustainable development can coexist with the natural environment and the cultural traditions that St. Martiners choose to maintain.

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August 25th, 2011 by Marc AuMarc

If you want to see a brown widow spider, head straight to the green fence that surrounds the Grand Case airport runway at the end near Hope Estate. For whatever reason, it’s extremely popular with this relative of the infamous black widow spider. Each metal fence post will have at least a few of these spiders, and often a half-dozen or more. Elsewhere on the island it isn’t hard to find, but I have yet to encounter a spot where it’s anywhere near as common.

Also featured below are a variety of insects, spiders, snails and lizards, mostly found around Grand Case.

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August 24th, 2011 by Marc AuMarc

After being away for a couple weeks, I returned to find the sargassum that had been washing up on the beaches of St. Martin has accumulated to a surprising degree. Sargassum is seaweed, and typically refers to a couple species in the genus Sargassum that live in the open ocean. This is unlike many macroalgae, which are attached to the bottom in shallow waters.

The Sargasso Sea in the North Atlantic Ocean is, of course, named after this alga. For the most part, currents surrounding the Sargasso Sea keep the sargassum in that area. The seaweed provides food and cover for certain marine animals, such as the loggerhead sea turtle.

At this point, I don’t know that there is a definitive answer about why such a large amount of sargassum is showing up in the Caribbean this summer. Some have noted that there are higher than average temperatures in the North Atlantic, which may have increased the amount of sargassum.

On St. Martin, primarily the Atlantic-facing eastern beaches have been impacted. In Grand Case, for example, one would have no idea that anything unusual was going on. Below are some photos from the beach at Grandes Cayes, where there are some pretty significant accumulations. When decomposing, the hydrogen sulfate that is released smells unpleasant and may pose some threat to those with asthma or other respiratory conditions.

What’s next? It’s tough to say. Removal from the beach is difficult without also removing sand, and heavy equipment would likely destroy sea turtle nests. As long as it stops accumulating, which seems likely, then it should biodegrade naturally over time. In the meantime, it’s a boon to isopods and other beach denizens that can eat it.

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August 1st, 2011 by Marc AuMarc

Underwood’s spectacled tegu (Gymnophthalmus underwoodi) is a small lizard that seems to be a recent arrival on St. Martin, probably within the last ten to fifteen years. It is named after the influential herpetologist Garth Leon Underwood. Amongst other things, Underwood revised the classification of Anolis lizards in the Lesser Antilles in the late 1950s. Originally just collecting a few specimens for a colleague, he undertook the revision when it became clear that many of the classifications, most dating back to the 1800s required an update. This was in part facilitated by the collection of live specimens, whose distinguishing features were much easier to discern than those of the stuffed museum specimens used in earlier taxonomic efforts.

Underwood’s spectacled tegu is probably originally from South America and likely brought to the Lesser Antilles inadvertently. It is parthenogenic, so all individuals are female and can lay eggs without being fertilized. This, along with its small size, probably contributes to its ability to spread to new islands. This family of lizards is referred to as “spectacled” because they have a transparent lower eyelid, allowing them to see through it even when it is shut.

On St. Martin, this lizard is closest in size to the dwarf geckos and closest in habit to the ground lizard. I have seen them most frequently in grassy lowland areas and rocky beaches (the dwarf geckos generally prefer forest floor leaf litter). The impact of this lizard on native species remains to be seen. In its current habitat, it probably competes primarily with juvenile Ameiva plei for food, while its presence in the forest would put it in competition with the two species of dwarf gecko.

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