Sunday, January 27, 2008

International Year of the Reef

2008 has been designated by ICRI as an International Year of the Reef, so today's blog is dedicated to IYOR!

Two weeks ago, I went out with the Looe Key Reef resort. They hosted the trash cleanup last December, so I felt like rewarding them for protecting our reefs. It was just a small group of 5 divers and 1 snorkeler, which gave me a chance to meet all the friendly folks. One of my dive buddies was Stefan, who has copyright on all these photos in today's blog.

Looe Key Marine Sanctuary was created in 1981 to protect what is considered to be one of the more spectacular reefs in Florida. It's a nice, shallow reef, with a max depth of only 30ft. It is named after the H.M.S Looe (the 3rd), which was a 42 cannon government-sponsored privateer frigate. On Feb 4 1744, the Looe spotted a small Spanish vessel that was identified as a former British merchant ship. They captured the ship and began towing it back, but in the dark of night they crashed into this reef; even after dumping all the cannons and ballast, the ships could not be freed and the 274 crewmen all crammed into longboats for the long haul back to Jamaica.

The reef is a Spur-and-Grove formation, which means the corals grow along ridges (spurs) and the groves are channels of sand. Spur-and-Grove is a characteristic pattern of shallow reefs, but I don't know why they form that way. My guess is that as corals grow higher, eventually a storm breaks loose some large fragments which begin banging around and destroying other corals. The healthy coral continue growing up, leaving the rubble in a trench that increasingly becomes the danger zone, eventually wearing it down into a sand channel. Considering most of the groves run parallel, it seems like wave action is more important than local topography, and makes this pattern appear on nearly all shallow reefs.

Coral reefs are formed through the slow, patient growth of Stony Corals. The importance of these reefs cannot be understated; they are some of the most diverse and productive ecosystems, but also over eons of time create land. The Florida Keys themselves are the top portions of the reefs from 7,000 years ago, when sea level was higher, and the current living reefs offshore are the breakwater that keeps large ocean waves from destroying the low-lying islands. In Texas, ancient Permian reefs are the backbone of our highest mountains in Guadalupe National Park. Stony corals create these massive landforms by one tiny animal at a time, each grabbing carbon dioxide from the water, combining it with Calcium to form their skeleton. The photo here is of Mountainous Star Coral, one of the more important reef builders in the Caribbean.

But the reef is also critical habitat for many species of fish. Most fish use the reef when they are young, since it provides lots of hiding places. However, some fish, such as this sneaky Spotted Scorpion Fish, live their entire lives on the reef. The Scorpion, along with Stone and Frog fish, use very cryptic coloration to lie in wait for something small to swim in front of them and literally GULP them up!

Every coral reef is visited by a very distinctive type of fish, called Parrotfish. These fish get their name from the fused row of teeth in their powerful jaws, which resembles a bill. Parrotfish have such a powerful CHOMP that they literally take bites out of rock and coral. This Blue Parrotfish is an uncommon fish to see, but he also has the large "bill" for the mouth. The juvenile Blue Parrot looks nothing like this; they are small, slender pale-white fish with a yellow head. The most common to see is the Stoplight Parrotfish, who get their name because they change color from red to green! Parrotfish are also one of the few fishes that are known to sleep, they literally lie down in a quiet place, pull up a mucous-blanket, and dream of algae salad.

I probably don't need to tell you the name of this fish..... that's right, it's a Neon Goby! Oh, you were staring at the Barracuda with the sharp, pointy teeth? Well look closer, near his "eyebrow" is a tiny, neon-blue fish. This barracuda is visiting the reef's equivalent of the dentist, which is known as a "cleaning station". Many large coral & sponge formations are inhabited by a type of Goby or Shrimp that specializes in cleaning gunk and parasites off other fish. The barricuda will sit patiently with his mouth open and let these tiny fish swim in and out to clean their teeth and gills. This strange behavior is a form of symbiotic mutualism; big fish keep healthy and the cleaners get a tasty snack.

Another strange animal found on the reef are Christmas Tree Worms. Somehow they find a way to burrow into coral and make their homes. They extend these modified gills above the surface to catch small particles of food. I really like 'em because they come in such a variety of colors and patterns; why do worms care how pretty they look? They're also very alert to motion or pressure changes, 'cause if you get too close - ZIP - they all yank their Christmas Trees back inside the house and become instantly invisible! Other free-swimming marine worms, like nudibranchs, are so vividly colorful they are like the butterflies of the oceans.

Sponges are another weird animal; really they are a loose colony of animals like a coral, yet they build often complex structures and come in a bewildering variety of shapes, colors, sizes, and textures. Sponges are filter-feeders; they take water in from the sides and slowly expel it from the large opening, catching microscopic bugs to eat. In the center an orange Giant Barrel Sponge, which can grow big enough for me to hide in! The vibrant green branching stuff in the foreground is also a sponge, the Green Finger Sponge. That's another thing I like about sponges, their names are also accurate descriptions -- compare that to stupid fish names, like the Spanish Hogfish above the Barrel Sponge; he doesn't resemble anything like a hog and I've never heard it speak a word of spanish. My favorite coral is behind the Barrel Sponge, it's the Symmetrical Brain Coral. I appreciate the intricate and alien mazes that brain corals make, and they are another important species in reef building. Growing at the right-base of the Barrel sponge is a Split-Rope Sea Rod, and the feathery-duster-looking thing behind it is a Sea Plume -- both being common types of Octocorals. Often these are called soft-corals, but that is incorrect: these guys are Gorgonians (their hair are made of 8 tiny snakes).

Here is another quiz: what fish is this? That's right, it's a remora! (look under the belly of the shark). Surely one of the highlights of the dive were seeing all the large fish, such as the Goliath Grouper, a couple of sleeping Nurse Sharks, and the stingray hiding in the sand (photo is above, flying away). We also saw a pair of Reef Sharks that were actively swimming about. They circled the three of us, but since we didn't act like food, they left us alone. Sharks don't have the best vision, but will often attack swimmers on the surface because they resemble wounded prey. It's probably not advisable to have stinky chum in your pocket either. I also saw 2 large moray eels and a spotted moray, which are always interesting fish to watch.

The absolute highlight of the dive was swimming alongside this very tranquil Hawksbill Sea Turtle! Sea Turtles are now very rare, since people have gone crazy eating adults, eggs, and then "developing" the nesting beaches. They are beautiful animals to watch swim, and are some of the most ancient survivors of evolutionary history -- their design is almost unchanged for over 150 million years. Another thing I like about these friendly beings -- they are the only known predator of stinging jellyfish!

Bye for now!
-- Mangrove Tom

Saturday, January 26, 2008

Farewell, Key Largo

Sorry for the delay in updating the blog. Time moves strangely in the Keys, sometimes slithering away under the rocks before you realize it. We spent the past two weeks again at Crocodile Lake National Wildlife Refuge, sweeping transects along the area. The photo here is a great landmark to search for if you're using Google Earth; it's locally refereed to as "Whiskey Bottle Lake", because it's artificial shape looks exactly like a bottle. The photo here is of the "neck", where Ralph said Crocs often hang out. I never had the chance to see one, but only had one opportunity to visit it. If you don't have Google Earth, you can refer to this topo map; in the upper right, the lake is shown as a rock quarry, and our transects were done about 1 mile to the southwest. The Keys generally do not have much topographic relief, but this area was once slated for development, and in areas where they were dynamiting canals, there were huge boulder piles 30' tall. We dubbed one Mt. Croc, since we believe it to be the highest point in Key Largo. It's tricky crossing, especially carrying a bottle of Garlon, a 30lb bag of lead tree & latherleaf seeds, handsaw, compass/trimble, and in the rain.

There's also sinkholes. Once while regrouping by the truck, a local stopped by to chat and warned us to stay within shouting distance since there's some pits that get covered with sticks and leaves and can trap someone. I personally saw an uncovered one with ~15ft vertical drop, so I believe him! One of the more unusual experiences was treating Queensland Umbrella trees that grew atop the boulders. It's a beautiful tree, with roots that grasp the bare rock. To our knowledge, it was the first time that a grove of those trees had been found in the interior of a hammock. All transects that crossed to old development encountered huge swaths of invasives, most we hadn't come across, such as huge Royal Poincina trees. Here is a great photo of Toto, the mattock meister, standing atop a mound of Sansevieria inspired by our ecological progress! He hauled in that mattock over 1 mile across very challenging terrain, which in itself is an accomplishment! I don't have as many pictures as I'd like of Croc Lake, because it rained often enough to make me worried about the health of the camera.

We saw a cornsnake and a black racer, but no pythons. On our last full day there, we spent the afternoon at a conference organized by The Nature Conservancy on Marathon Key, where a new program to combat the pythons was announced. It builds upon the existing "Don't Let it Loose" program that is receiving federal funding to control invasive animals in Florida. FYI: here is a fun quiz that covers hardwood hammock species (on the last page). Dr. Snow from the Everglades presented his research on the python problems in Florida (which included a slide titled, "Snakes Under a Plane"). Some interesting facts are: pythons can eat up to 80% of their body weight in one meal (my equivalent would be eating a 136 lb burger! URP!). They can grow fairly quickly and get huge; the public took notice when an 8ft Burmese was found close to the local elementary school in Key Largo! Readers of my blog will be glad to know that I am not supposed to handle wild pythons, my job is to call 888-I'VE-GOT-ONE, and then take a picture. I'm not too worried about snakes in general, having spent gobs and gobs of time outdoors in prime snake habitats. I've seen lots of rattlers, copperheads, moccasins, and other non-poisonous snakes, and not one has ever been aggressive. According to a research article I read in Natural History, nearly all snake bites occur to young males (20-30 yrs old) that were hunting; 50% of those accidents involved drunkeness, and another 30% involved handling of the snake... so one might argue that maybe snakes are just trying to help humans clean out our gene pool. However, Dr. Snow presented two slides that managed to strike fear into my heart: the 1st slide showed wild python kills per year... which was flat until 2003, when suddenly the chart begins an exponential growth curve. That slide indicates that pythons are essentially out of control in Florida, and there's no estimate to how where the population will peak (some places in Asia have densities of 1 python per hectare!!!!). Wow, so it looks like Florida has a serious snake problem... but the next slide was even scarier; it was a projection of the python's potential habitat in the USA, and it includes the entire south-east USA, from Texas to the Carolinas!

After that meeting, we took out truck to deliver a couch. We picked it up at the Dive Museum in Islamorada (the house is above the museum). How'd you like your home to look like this? There were paintings of corals and whale sharks too, but I've never seen a manatee, so I they are my favorite. Tomorrow, I'll post some photos from my last dive trip. Meanwhile, it's time to catch up on the news; the primaries are going on in Florida, but I've not been able to keep up with the "real world".

Sunday, January 13, 2008

Snakes on a Plane!

One book I read last year was "And No Birds Sing: The Story of an Ecological Disaster in a Tropical Paradise". It's an interesting story on how invasive species can unexpectedly and quickly create a crisis. These thoughts were forefront in my mind as Steve from Florida's Fish & Wildlife handed us "Python Hotline" cards. One of Steve's important charges is the welfare of the Key Largo Woodrat. These cute animals build nests in rockpiles or other debris, using sticks and grasses to line a cozy nest and gather seeds. Recently, a huge python was found with no less than 7 rats all lined up in its gullet. Considering there are fewer than 500 woodrats, it's pretty clear that this predator is creating an imbalance.

Ralph is one of the highly energetic and dedicated volunteers that work's with Steve on how to help the woodrats. He has devised artificial nesting cavities with good success. The hard-to-get photo of him shows him demonstrating his technique for tracking another exotic invasive even deadlier than the python; the house cat. He uses the sand to check for cats using the path, then traps them to hand over to the shelter. Despite both Steve and Ralph being animal lovers, the pythons really don't have a future if they're caught - they are slowly chilled in the fridge to sleep and then killed. Other team members in the photo are Bossman Hau (aka, 'the Narwhal'), Topher, and Toto.

Ralph also said there are crocodiles in the nearby lake, so I'll try to get a picture of one this coming week. We did see the remains of one poor croc on the shore, and I took a photo of the bony plates left behind (I don't think alligators have these plates). Living in the trailer was nicer than expected; there was even a TV (with one channel). The hammocks there are a nice change of pace too; lots of different native plants. Lead tree is the biggest problem we've encountered, and we've knocked out thousands of em. We also came across a huge stand of 30' tall Burma Grass. We also had the benefit of working with 2 volunteer students from Oberlin college; John and Mike.

Friday, it rained all day, but I was able to sneak out for some adventures. Saturday, i attempted to track down US geodesic benchmarks to report their status. I visited the site of the abandoned ferry on No Name Key, and found the foundations of an old house and water tank. Unfortunately, I didn't find any of these benchmarks, except for the ones already reported as found on the Bogie Channel bridge. I did get the chance to do some birdwatching and exploring; seeing a blue-gray gnatcatcher and a pair of yellowlegs in the swamp. The yellowlegs in this photo are only about 100' from where the benchmark listed above is supposed to be, but I saw no sign. Maybe I'll return one day with waders!

Today, I bought passage aboard a dive boat to Looe Key for 3 dives. There were only 5 other divers aboard. One couple was from New York and studied invasive plant ecology! He had even worked some in Big Bend and Santa Monica. (sing: it's a small world). I dove with Brandon from New Jersey and Stefan from Big Pine. Brandon saved my dive by letting me borrow a flipper, since my strap broke! We had great weather, visibility, and hot dogs.

We saw HUGE barracuda, stingrays, dolphins, and I was able to name 48 species of fish (and I'm no ichthyologist/fisherman!). There were lobster and sea urchins hiding in nooks, and snooks were in school, massive green parrotfish, sleeping nursesharks, 3 green morays, 1 golden-spotted moray, and lots of others! The highlight was following along with sea turtle (hawksbill?), and being circled by 2 reef sharks!!! I'll have to compile my dive notes soon and submit a report to REEF. I also hope to update this blog with some underwater photos. Maybe I should buy a housing for my Canon?

I noticed it might snow in Dallas this week... but we'll be in the 70's here in the Keys!

This last image is of some lizards who share the shelter of a woodrat's nest:
Over and out! -- Mangrove Tom

Saturday, January 5, 2008

Winter Arrives in the Florida Keys!

Along with the lower 48 states this first week of January, Florida was hit with the powerful cold front. It didn't snow or freeze, but the wind stayed very strong for over 3 days. It churned up the bay waters, which are still murky two days after the waves finally quieted down. Key West broke the coldest temperature record, which was set in 1898! Despite this week of cool weather, the winter has so far averaged above normal temperatures.

One strange aspect of the cold is the effect it has on our cold-blooded critters. Iguanas, anoles, and other lizards were falling out of trees! We stumbled across a cold-benumbed iguana last week in our sweep through the Blue Heron Hammock. These lizards are considered a nuisance, so we captured it and had placed it in a bag to take to the Florida Fish & Wildlife and make it their problem -- our first invasive animal we "treated". We went back to work, leaving the iguana in the shade of the truck. When we returned 4 hours later, the iguana had escaped. The day warmed up enough for it to realize it was in trouble and needed to get moving.

We're almost done sweeping through that hammock, which is good news, since it is tough going and wearing us out. It will have to wait awhile though, since we'll be working in Key Largo and Tavernier Keys for the month of January. The iguana was good practice, since we may well be encountering the dreaded pythons that must be captured (not by us, we just call in experts and help). Of course, the crocs and alligators, being native & protected species, are welcome to be fruitful and multiply. Alligator populations have rebounded nicely, however the crocodiles have not.

Over the weekend, I was able to do some birdwatching and was lucky enough to see my first life-list bird of 2008: a yellow-throated warbler chipping in the cold wind atop a coconut tree. Other birds I saw for the first time in the Keys were: yellow-crowned night heron, northern cardinal, and a flock of blue-winged teal. Lots more tourists seem to be down this time of year too, probably escaping the cold north just like the warbler.

Time to pack for my adventure next week!