Dispatches from the Gulf: Film examines the effects of Deepwater Horizon oil spill

The 2010 Deepwater Horizon disaster may no longer be a buzzword in the media, but the effects of history’s largest oil spill on the ecosystem of the Gulf of Mexico are still on the minds of marine scientists around the world. Gulf seafood seems to be recovering, but biologists are keeping a close eye to the seafloor, where much of the oil has settled into the sand. Take a closer look at the lingering effects of the spill Tuesday night at the Houston Museum of Natural Science with a special screening of the science documentary Dispatches from the Gulf.

This April 20 will mark the sixth year after the massive failure and subsequent explosion of the Deepwater Horizon, also known as the Macondo Prospect, an offshore drilling platform 50 miles off the coast of Louisiana. The blast claimed the lives of 11 workers and from a depth of 5,000 feet, pumped more than 200 million gallons of crude oil and natural gas into the Gulf over a period of 87 days. A month after the disaster, BP, the operator of the prospect, announced it would commit $500 million over 10 years to the study of the effects of the spill.

GULF OF MEXICO - APRIL 21:  In this handout image provided be the U.S. Coast Guard, fire boat response crews battle the blazing remnants of the off shore oil rig Deepwater Horizon in the Gulf of Mexico on April 21, 2010 near New Orleans, Louisiana.  An estimated leak of 1,000 barrels of oil a day are still leaking into the gulf. Multiple Coast Guard helicopters, planes and cutters responded to rescue the Deepwater Horizon's 126 person crew. (Photo by U.S. Coast Guard via Getty Images)

GULF OF MEXICO – APRIL 21: In this handout image provided be the U.S. Coast Guard, fire boat response crews battle the blazing remnants of the off shore oil rig Deepwater Horizon in the Gulf of Mexico on April 21, 2010 near New Orleans, Louisiana. An estimated leak of 1,000 barrels of oil a day are still leaking into the gulf. Multiple Coast Guard helicopters, planes and cutters responded to rescue the Deepwater Horizon’s 126 person crew. (Photo by U.S. Coast Guard via Getty Images)

In addition to the tragic loss of life, many environmentalists expected a total collapse of the ecosystem leading to further economic effects in the fishing and seafood industry, yet as early as five years later, CNN reported fish landings had returned as well as the oyster population.

“According to the Food and Drug Administration, tests on edible seafood show no excess hydrocarbons in the region’s food supply,” Drew Griffin, Nelli Black and Curt Devine of CNN.com reported. “The spill’s effects on other species are less clear. … But perhaps the greatest unknown is what, if anything, millions of gallons of oil on the deep seafloor are doing to the overall environment of the Gulf itself.”

Our own Associate Curator of Malacology Tina Petway is one of the scientists keeping watch. She flew over the disaster while the oil was still free-flowing, visibly bubbling above the surface of the water from the break at depth. To her, the Texas coastline is the least of her concerns.

The Deepwater Horizon disaster created an oil slick visible from space.

The Deepwater Horizon disaster created an oil slick visible from space.

“The oil can wash up in globs, which is bad for folks walking or playing on the beach,” Petway said, “but the real problem is that the oil stays in the environment even though they have removed a huge quantity of it. A lot of it has sunk.”

On the bottom of the Gulf, the oil has created a mat of tar, leaving the sand impenetrable to oxygen and light, Petway explained, eliminating everything beneath the mat from the habitat. Chemicals from the oil are leaching into sandy and muddy seafloors, making hydrocarbons difficult, if not impossible to dissolve or wash away.

“Just because you don’t see anything on shore anymore doesn’t mean it’s not still out there,” Petway said. “Ongoing research is being done as to the effects, and it is constantly being updated.”

Watch the screening of the science documentary Dispatches from the Gulf Tuesday, Feb. 9 at 6:30 p.m. in the Wortham Giant Screen Theatre at the Houston Museum of Natural Science. The film will recap the unprecedented response effort following the disaster and delve into the research of the Gulf of Mexico Research Initiative (GoMRI). Tickets $18, members $12. For one night only!

You can learn more about the delicate Texas coastal ecosystem at the Hamman Hall of Texas Coastal Ecology.

Food chains link the creatures of coastal ecology

Don’t stick your hand in that shell! You don’t know who might be home. It could be a carnivorous snail or a “clawsome” crab. Take a look at our Texas state shell, the lightning whelk or left-handed whelk, which feeds on bivalves like oysters and clams. Perhaps the snail that makes the shell is still hiding inside, or perhaps the shell is home to a hermit crab. Unlike most crabs, hermit crabs use the shells of snails as homes to protect their soft bodies.

Hermit Crab

Hermit crab taking residence in an empty lightning whelk shell.

Texas is home to some fascinating creatures, and our coast is no exception. In addition to the Gulf side beaches, there are salt marshes, jetties and the bay to investigate. Our coastal habitats are just waiting to be explored, and with the right gear, you can see organisms at every trophic level. (You knew I was going to talk about food chains, didn’t you?) 

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Lightning whelk snail retracted into its shell, operculum blocking the opening.

Most folks will notice some of the upper-level consumers: birds like pelicans and gulls. Who could miss the gull snatching your unattended hotdogs? Or the pelicans plummeting into the water face first to catch fish? Maybe you’ve noticed fishermen along the beach as they pull in small bonnethead sharks. Some animals may require good timing and tons of mosquito repellent to see, like our rare and critically endangered Kemp’s ridley sea turtle. If you pay attention, there are even rattlesnakes catching mice that are feeding on insects and plants in the dunes!Food Web

As you follow a food pyramid from the apex down to the base, top predators like humans and sharks feed on the organisms in the level below. There you might find the larger bony fish we feed on, like redfish or snapper, and below them you can find some of the crustaceans and mollusks they feed on in turn. Crustaceans, like our blue crabs, stone crabs, and the smaller ghost crabs, often scavenge in addition to feeding on mollusks, worms, or even plant matter. Many of our mollusks are filter feeders, like oysters, pulling algae and plankton from the water. Finally, at the base of the food pyramid, there are the producers. The phytoplankton and algae make their own food with energy from the sun.

A food chain pyramid is a great way to show different types of food chains on one example. I used a pyramid created by my friend Julia and drew examples of food chains from our coast on it. One side has the trophic levels on it and the other three sides have example food chains. What’s on the bottom of the pyramid? The Sun, of course!Pyramid

Coastal ecology isn’t just about sand, shells, and dodging gulls. It’s also about the interactions between plants, animals, and their environment. The plants anchor the dunes, the dunes protect and replenish the beach sand, the sand houses animals like mole crabs and mantis shrimp, and we get to enjoy it when we protect it.

If tracking home beach sand in your shoes, car, towels, and suits doesn’t excite you, our new Hamman Hall of Coastal Ecology may be just the air-conditioned trip to the coast you need on a scorching summer day in Texas. Members, come join us Memorial Day weekend to see wonders of the Texas coastline!

Tales from Tanzania: Oh, the things you’ll find in a caldera

On the next leg of our trip, we visited the Ngorongoro Conservation Area.

NgorongoroNow, you may ask, “Nicole, your last adventure was in a national park, and this is a conservation area — what’s the difference?” And I’d answer that a conservation area has people living on it, whereas in a national park, no permanent settlements are allowed. The Maasi people live in the Ngorongoro Conservation Area with their cattle full time. They have been allowed this exception since they do not hunt. According to their traditional customs, they are only allowed to eat cow, goat and sheep so the wild animals in the crater have nothing to fear from them.

The Ngorongoro Conservation Area is especially interesting, as it contains the largest unbroken caldera in the world. It was created by a volcano, which has now collapsed. Before it collapsed, the volcano would have been much, much higher than Kilimanjaro.

The formation of a caldera

The crater has given rise to a variety of ecosystems due to its geography and sheer size. Moisture is pushed in from the ocean in the east, but it gets caught at the rim of the crater. The outside eastern edge of the crater, therefore, is home to a thick highland forest full of tropical birds. The west side of the crater only gets rain in the rainy season and most of the time looks something like dry west Texas.

Interestingly, the crater is responsible for most of what we have seen and what we will be seeing on this trip. The eastern edge of the crater is so dense that natural springs flow into Lake Manyara rather than the crater, keeping it green and providing a source of water for animals.

Looking to the west, when the volcano erupted 2.5 million years ago, the wind blew the volcanic ash to the Serengeti, which caused hard-packed earth that only the acacia can penetrate.

Later in the evening, we were able to talk to crater naturalist, Yotham, at our hotel. He was very surprised to see several of our pictures (we always knew we were looking at something awesome if one of the driver guides took out a cell phone to take a picture).

In particular, Yotham was surprised to see our shots of the Little Bee Eater, as they usually don’t come into the crater. Instead, they live in the highland forests on the outside western edge.

DSCN1517DSCN1205As we continued to go through our shots, he indicated that we had, in fact, had a very, very good day of observations.

Here are some of the highlights: 

Hyena kill: We arrived right after the wildebeest was taken down. Just out of screen are several other hyenas and 20 or so vultures waiting for their turn at the carcass. The eating hyena kept dragging the carcass away so it could eat without feeling crowded.

DSCN1604Ostrich: So, I learned something new today. When you see a male ostrich with a bright pink neck, it is feeling frisky. A male ostrich with a white or gray neck is not currently interested. Female ostriches are very beautiful but very differently colored than the male ostriches.

DSCN2036DSCN2048Serval: This picture is a bit miraculous. The serval is normally a nocturnal animal, so it was amazing to see it out during the day. AND THEN IT STARTED HUNTING. AND IT WAS AWESOME.

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Tales from Tanzania: Witnessing the resiliency of nature at Lake Manyara National Park

Our first game drive through the 285 square miles (460 km2) of Lake Manyara National Park did not disappoint. Covering 89 square miles (231 km2) of the park, Lake Manyara is a salt lake ranging from 20 to 50 feet deep. The lake’s high alkalinity comes from sodium bicarbonate, which leaches out of the volcanic rock in which it sits.

When we arrived, the surrounding area had recently flooded, causing serious changes to the landscape in several ways. The most drastic had come from landslides so powerful they had nearly covered the original ranger office.

When the area flooded, the level of the lake also rose, causing the surrounding area to have significant deposits of sodium bicarbonate. This sudden change killed all of the trees in the flood area.

However, by the time of our visit we were able to witness the incredible resiliency of nature, as the area had already started to heal itself. This is helped by the many underground springs which bring in fresh water, giving the animals clean drinking water and clearing out the salt deposits. The grass is already making a comeback and the rangers are confident that the trees will soon follow.

While the flooding was terrible in so many ways, it might have done the area good, as it gets very little rain. Each year 75 percent of the lake evaporates in the dry season, which concentrates the salts. Hopefully the floods diluted the salts, if only for a short period. And as you can see in the following pictures, the animals hardly seem to have minded the flooding.

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The baboons in Africa amazed me. As far as I can tell, they are the equivalent of a diurnal raccoon in the states. They are smart, quick on the uptake, like eating leftovers, and aren’t afraid to come take something that is shiny or smells good. We didn’t have any troubles with them, but we were warned not to feed them and were told tales of cameras and other treasures lost to the unsuspecting.

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The second coolest things we saw that day was a Verreaux’s Eagle Owl with a fresh kill in its talons. It was surprising to see a diurnal owl here as most of ours are nocturnal.

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Being part of the science dork crew from the Museum, the coolest thing I think we saw that day was a hippo carcass. I was in a truck with a large animal vet that day, Mary Sue, so we spent a good bit of time trying to CSI the hippo. A clear indication that large predators are in the area, the hippo carcass was picked clean — except for the skin, which was too thick for anyone to eat.