Tuesday, August 31, 2010

Transporting cownose rays

Guénäelle Rubin, Delaware Expedition

Transporting 30 cownose rays is as easy as it sounds.

The first step was to haul a holding tank onto a fishing boat in Cambridge, Maryland, then catch the rays and place them into the tank. Lucky for us, the fishermen whose boat we were on have generations of experience catching and hauling fish, so we had plenty of help and good company for this first step. When the fishermen pulled up the weir net, about 40 rays splashed the water with their wings. As we had only expected to see maybe 9 or 10 in the net, it was an amazing site to see.

Here, a cownose ray is being placed into the tank. The lid, which looks like a slice of swiss cheese, is there to prevent the rays from jumping out of the tank and hurting themselves.

Chris D. checks the oxygen level of the tank.

Once the fishermen checked all their nets and collected buckets of menhaden and blue crabs, it was time to return to shore. The rays were carefully transported 2 by 2 into a larger holding tank in NEAq’s box truck.

I sat in the back of the truck for a portion of the 2 hour drive and learned how challenging it can be to continually monitor the oxygen levels of the tank all while convincing myself that motion sickness does not exist.

The inside of the truck has no windows and therefore no way to hold my gaze on a green calming landscape. Just a loud rattling noise and the splish-splashing of tank water can confirm that we must, in fact, be on some kind of road. Luckily, aquarist Chris was there to manage the care of the tank!

We finally arrived in Lewes, Delaware to transport the rays into a large holding tank.

This is where the rays will stay until we are ready to make the long haul back home to Boston.

The duration of this drive is expected to be about 10 hours, if all goes smoothly.
During this time, aquarists take turns riding inside the box truck and monitoring the holding tank for pH, ammonia and oxygen levels. These tests are done constantly throughout the drive so there is no time for "punch buggy" or Mad Libs.

Megan and I need to return to the Aquarium before the cownose ray transportation mission is complete. However, Dave Allen, another fellow educator at the New England Aquarium, will be coming down to Maryland to help with the transport of the rays. Stay tuned for Dave’s cownose ray blogging adventures!

Until next time…

-Guénäelle (excited about notebooks and hotels)

- Megan (enjoying a yummy hometown Maryland meal with Dave W. and Chris P.)

Monday, August 30, 2010

Clear Water & Mighty Makos

My very first encounters with sharks happened right here in the waters off New England. It was about twenty-five years ago that I met a shark scientist named Wes Pratt, who worked for the National Marine Fisheries laboratory, Apex Predator division in Narragansett, Rhode Island. Wes had built his own shark cage and was diving offshore with some of his colleagues, like Greg Skomal, who continues to work with sharks today and has recently done some cutting-edge research with several species. After pestering Wes for some time, I was invited to join the group and was absolutely thrilled. The sharks we most often saw were blue sharks. These were exhilarating days filled with anticipation as I steamed offshore and spent hours drifting in the chilly water, watching stunning indigo blue animals nosing through the slick. Occasionally we saw a basking shark and once saw a couple of dusky sharks, but mostly it was the beautiful blues.

A female mako shark, about 4 feet in length, swims near the surface offshore of Rhode Island/New York. (Photo: Brian Skerry)

We always dreamed of seeing makos, as these animals had almost legendary status as one of the fastest and most powerful species of shark in the sea. Wes had a vanity license plate on his old Volvo that said “ISURUS” which is the scientific name for makos and even used to sign his hand-written letters to me "Clear Water & Mighty Makos, Wes." As we sailed offshore on every trip we inevitably would talk about how maybe this was the day. And each day Greg Skomal religiously predicted a four o'clock mako but as 4 p.m. rolled around, the elusive fish rarely materialized. In all the years I made these shark dives, I think I saw two makos and both stayed near the boat for only a few seconds.

In the years since then my work has taken me around the globe photographing sharks in countries worldwide. I have longed to get back to my home waters, but being in the field on assignment nearly eight months each year left little time for shark diving in New England. A couple of years ago, I was contacted by an underwater videographer named Joe Romeiro from Rhode Island. I had seen Joe's shark films and they were beautiful. He had a true artist's eye and his films were respectful of animals and brought viewers into their world for an intimate view. Joe was doing a fair bit of shark diving locally and invited me to join him, but as usual, my schedule simply never permitted me to do so. But finally last week, the day after I made my last blog post ("Thinking About Sharks"), I went diving again for sharks in New England.

Joe had told me he was having great luck with not only blue sharks but with makos. I was amazed to hear this given the few sightings I had all those years. But Joe had been doing his homework and was especially tuned in to these animals. And he was also putting in the time it takes to learn. So off I went to spend two days off the coast of Rhode Island ... and low and behold ... I saw three mako sharks. Incredible! The first one showed up on day one about 45-minutes after we stopped the boat. I was blown away!

Two of the Makos stayed with us for a little while, one sticking around for several minutes. I got in the water and was able to have some wonderful close encounters. The shark was a small female and was stunningly beautiful. Her coloring was bold and vivid and she didn't appear to have a scratch on her. She moved with speed and with power, exuding the supremacy she clearly knew she had in the sea. I fired a few frames on my camera trying desperately to make sure exposure was correct and composition was good. Before my heart could stop racing, she was gone and I was climbing back on board the boat.

Like those diving days decades ago I was exhilarated and so happy to be back in these wonderfully cool waters with awe-inspiring animals. I am certain that much of our success had everything to do with Joe's expertise, but I would also like to think that perhaps mako sharks are doing a little better, that their numbers might be slightly increasing. I'll have to talk with some of my researcher friends like Greg to see if data exists. In the meantime, I'm looking forward to my next shark dive. And for now, I'll borrow a little from Wes and just sign off ...

Clear Waters & Mighty Makos,

Saturday, August 28, 2010

Eureka, a horseshoe crab!

Guénaëlle Rubin, Delaware Expedition

Eureka, a horseshoe crab! Dave is carefully holding the one single horseshoe crab found in the weir net. (Learn more about weir nets and why we're in Delaware observing the haul back in this previous blog entry!) Although horseshoe crabs have a menacing appearance, they are quite harmless. Horseshoe crabs do not sting, pinch or bite.

This was the biggest horseshoe crab that I had ever seen! It was definitely a female, since female horseshoe crabs are significantly larger than males. This is about the time of year when horseshoe crabs finish laying their eggs ashore, so the fishermen were not surprised to see one in their nets. Horseshoe crabs can lay as many as 120,000 eggs in one season! Although that sounds like an awful lot, many of the eggs are eaten by migratory shore birds that pass over the Delaware Bay. Red knot birds, for example, rely on horseshoe crab eggs for food to survive their long and arduous migration of 9,000+ miles.

Horseshoe crabs are life-savers for humans too. Almost all medical injections such as vaccines are tested using horseshoe crab blood since their blood contains a compound called Limulus amoebocyte lysate (LAL) that detects the presence of endotoxins.

You can see horseshoe crabs at the Aquarium at the Edge of the Sea exhibit. Come by sometime to see these amazing animals in person!

Friday, August 27, 2010

Diamondback terrapins

Megan Moore, Delaware Expedition

One of the species of animals that found their way into the weir nets were diamondback terrapins. Diamondback terrapins are a "near threatened" species of turtle that can live in a mix of fresh and salt (brackish) water. We have two diamondback terrapins in our thinking gallery on the second floor of the Aquarium’s main building. Prior to the turtles being listed as near threatened, the fisherman Chris would catch them to be sold to Asian markets for turtle soup.

The diamondback terrapins that we saw were all comfortably hanging out in the weir nets - possibly even snacking on some of the fish in the nets. In fact, before they pull up the nets the turtles can come and go as they please. But as they pulled up the nets the turtles then realize they’d rather be on the outside of the nets. They began to climb up the sides of the nets. It was rather comical to watch! This one turtle almost made it out before the net shook enough that it rolled back down. Here's some video of its valiant effort!

Diamondback terrapin swimming free from the nets

All their worry is for nothing because as soon as the fisherman can reach them they are picked up and released. Just like this guy.

Dave Wedge about to release diamondback terrapin back into the water

Because of their conservation status is was a good sign to see so many of them!

- Megan

Thursday, August 26, 2010

A Day in the Life of a Maryland Weir Fisherman

Megan Moore, Delaware Expedition

Wow! I have a new respect for fishermen.

Fishermen in boat

We had the pleasure of working with Chris, who gave us a small sample of his typical day. They rise early, about 3 am, to beat the heat and make sure they have enough time to get everything done. The early morning usually consists of checking all the weir nets for their catch of fish (usually menhaden) and then the late-morning/early afternoon is spent using the fish as bait to catch the beautiful and delicious blue crab.

Blue crabs

Occasionally Chris catches cownose rays in his weir nets and that's why we had the pleasure of waking up at 3:30 to join him.

Lucky us! Megan and Guenaelle on the boat

Chris had 5 weir nets that he set up this season. Weir nets consist of a strange formation of nets that give every fish that encounters the net a choice: Either turn one way and enter into the funnel of the nets or turn the other way and swim free. Here's a picture of what the setup looked like, though it might be a little tough to see since the sun wasn't up yet!

Weir net formation

Here's a closer look at the net. You can see diamondback terrapins poking their heads above the water. All of these turtles were returned to sea.

The best part about these nets is that all the fish that are caught in the net stay in water until they are pulled up. So if there were any fish or animals caught that weren't part of the targeted catch, they can usually be released unharmed. That means weir fishing can be a pretty environmentally responsible way to fish. (Learn more about other methods of sustainable fishing through the Conservation Department at the Aquarium.)

Here's a video of Chris and Joe pulling up the catch in the early morning light.

Pulling up the weir net

Menhaden catch in buckets

Check back later to find out what else turned up in their nets!

Monday, August 23, 2010

The Beginning

Megan Moore, Delaware Expedition

It was a little bit of a shock when I heard the news at 4 p.m. on a Tuesday that I would be leaving for Maryland at 8 a.m. sharp the following morning; but when I found out that the journey would involve going aboard a boat at 3 a.m. to catch cownose rays, the panic strangely turned to excitement. Cownose rays are a type of eagle ray that hang out in the Chesapeake Bay in the spring. They do have a venomous barb on their tail but they, like most rays and sharks, are not aggressive and won't sting unless they are threatened. You can find Misty, our current cownose ray, on exhibit in out Giant Ocean Tank.

Mystic, or Misty, in the Giant Ocean Tank

This blog will attempt to report the tale of the strange ways and the lengths we sometimes have to go through to bring the best fish to the New England Aquarium. These rays will eventually be one of the highlights of a future touch tank exhibit. For now, enjoy this video of Misty swimming in the GOT!

- Megan

Friday, August 20, 2010

Thinking About Sharks

I have been thinking a lot about sharks lately. I suppose these animals are never far away in my thoughts, but summertime seems to give these animals lots of attention and I've been thinking about them even more than usual over the last few weeks.

An oceanic whitetip shark off Cat Island in the Bahamas swims past a shark cage with shark biologist Wes Pratt inside. (Photo: Brian Skerry)

Much has been said and written over the years about these often-misunderstood creatures. Despite some very good magazine articles and television documentaries portraying sharks accurately, a common tendency is to continually show them as beasts whose only purpose is to attack humans. I've had the privilege of diving with and photographing sharks for over 25 years and have always found them to be spectacular animals that are quite different and far more complex than the one-dimensional public perception so often presented.

Caribbean reef sharks (Charchahinus perezii) swim over a coral reef in the Bahamas. (Photo: Brian Skerry)

Sharks are of course apex predators and possess tremendous speed and strength. They must therefore be highly respected. At the other end of the spectrum from being painted as monsters however, is the notion that they are friendly or playful animals. In my opinion, sharks should not be characterized as house pets or equated to any domesticated creature. They are wild animals that reign supreme in the sea. But it is important to understand that they are not out there just waiting to attack humans. Divers regularly swim with wild sharks and have amazing and exhilarating experiences. Caution must be taken and safety must always be paramount.

These regular encounters between sharks and humans show clearly that sharks are not monsters, but rather sophisticated creatures that have evolved to a perfect state of being for life in the ocean. Encountering a shark within its realm can be a life changing experience, for the better.

A large female mako shark being finned at shark camp near Santa Rosalia, Mexico. (Photo: Brian Skerry)

Sadly, we are rapidly loosing our chances of seeing a shark in the wild, because they are vanishing from Earth's oceans at an alarming rate. Each year more than 100 million sharks are killed, largely for their fins, which are used to make shark fin soup. I don't believe that such a slaughter of any animal would be tolerated on land, but because they live underwater and are fish, it goes often unnoticed.

Doomed by a gill net, a thresher shark in Mexico's Gulf of California is among an estimated 40 million sharks killed yearly for their fins. They add to the devastating global fish catch: nearly 100 million metric tons. (Photo: Brian Skerry)

Sharks have not changed in nearly 400 million years because since that time they have become perfect for life in the sea. My hope is that humans, who clearly have the capacity for change and to do great things, will evolve to a point where we no longer decimate fellow species with which we share this planet.

Brian Skerry

[Brian's recent post about the mighty mako includes great video of him diving with sharks! Check out Brian's TED talk embedded in this post. Brian also reported about sharks in the field during the 2009 Phoenix Islands Expedition and you can see more of his underwater photography on National Geographic here, here, here, here and here]