New Shark Science

Last week, Dr. Neil Hammerschlag University of Miami shark biologist and director of the R.J. Dunlop Marine Conservation Program, invited me on shark research trip out of Islamorada, in the Florida Keys. Joining us were a dozen high school students from the Miami Museum of [Science's Impact Upward Bound Program](http://www.miamisci.org/impact/impact.html" http://www.miamisci.org/impact/impact.html), to assist with the fishing, tagging and other research endeavors.
Sharks have been on this planet since before the dinosaurs existed. Beyond that we know too little about them except that the irrational demand for shark fin soup, among other issues, is wiping them out. Fortunately, a bill called the Coastal Jobs Creation Act is moving through Congress, which would improve fisheries management by paying veteran fishermen to do more cooperative research with scientists, restore habitat, and collect marine debris. While this bill was conceived before the Gulf oil spill, the types of projects that would be funded through the act are also needed to help hard-hit fishing communities. Meanwhile, you get a better understanding of the species for less money, greater faith in the management process, and healthier ecosystems. Click here to contact your Congressmen and ask him/her to support. (http://actionnetwork.org/campaign/jobsforfishermen_protectionsforfish.)
Neil's team is on a mission to learn much more to manage fishing for them sustainably, before it's too late to recover the 30 percent or more of all shark species that are threatened or near-threatened by extinction. They couldn't do it without the help of expert shark fishermen, such as our captain, Curt Slonim of Curtasea Charters, who has been targeting sharks in Florida Bay for more than 15 years. Buoy position are marked on the GPS, once deployed, to get a sense of shark species distribution and abundance across different habitats. This tiny computer is a pop timer. It records from the time the fish takes the hook to retrieval. The team has blood and tissue samples analyzed, to see, among other things, how stressed the animal became by reading lactate levels, dissolved oxygen and carbon dioxide. They want to be able to provide catch-and-release shark anglers with a "best fishing practices" timeframe in terms of promoting survivorship.
Wire chums bags are filled with bloody mackerel.
Graduate Intern Brendal Davis cinches down the trap lid tight.
Meanwhile, the team shares what they're learning by encouraging high school students to help with the research, and by creating a unique virtual distance education project to bring ocean exploration into classrooms via live online interactive wireless communications.
This immature male lemon shark was the second fish we caught. That's a battery-powered hose pumping water through its gills while the researchers tag it and collect biological data.
In more than decade of covering coastal conservation and marine research, I've never been on a trip that was so successful on so many levels.
Most sharks must swim to breathe. Water flows over the gills, and inside the gills are hundreds of feathery gill filaments. Each filament in turn has thousands of leaf-like lamellae, or flaps, which contain blood vessels. The blood absorbs the oxygen from the incoming water. The pump promotes survivorship, increases health, and improves release conditions.
Neil leads the kids in the good-luck hammerhead shark cheer.
But Fiona soon found herself wrasslin' with a big nurse shark.
Yep, her University of Miami coursework includes handling big sharks. Makes me want to go back to school.
Fiona wins the battle.
Brendal Davis' tattoos reflect who she is . . .
A young researcher, in her element, collecting data on sharks, and loving it.
Fiona's pretty stoked too, that she passed on a finance major, for marine biology. But as the intern, she gets to hold the shark's head still.
Data on length, sex and many other factors are assiduously collected.
A young, prospective researcher divides a fin clip sample into two parts for separate analysis.
Nurse sharks are among the most common species caught. There's no need to put them in the boat or insert the hose, because they can breathe while held still. Nurse sharks have the ability to pump water through their gills by forcing water down through by drawing it in through the spiracles.
Can remain motionless for periods of time, they have a spiricle comparable to a third gill or lung that helps pump water and breathe. They twist and roll and tail slap at the boat.
Brendal uses a tail rope to keep this "nursie" in line while samples are taken.
Neil negotiates around the engines while battling a bigger lemon shark.
They use a cable to lift the shark evenly into the boat, then immediately insert the hose. The last thing anyone wants to do is harm one these animals.
This lemon shark just seemed to abide the procedures by taking a nap on the gunnel.
Water pours through the gills of this young lemon shark. Lemon sharks are now protected in Florida waters. Catch-and-release only.
The young lady got to clip a tag into the lemon's dorsal.
A second, orange roto tag, other tag is "spaghetti" tag is inserted. Identification tags. Fishermen recapture and report it. The tags have different retention rates, sometimes they shed the tags and hedges bets. What do we know yet? We've recaptured blacktips, lemons and blacknose, sometimes on the exact same GPS position, we don't know what goes on between there, but it tells us that these National Parks are important for these animals, and there's no commercial fishing for sharks.
Between sets, Neil's team led the kids on a swim.
They took time for a quick swim by a nearby key. Even after catching sharks, they all jumped right in. It was a good to see that just a little interaction dispels the myth that sharks are ferocious man hunters.
For most of the kids, the trip offered them the first time to see and touch a shark. The R. J. Dunlap Marine Conservation Program has given field experience to more than 1,000 high school students, more than 60 University of Miami undergraduate and graduate interns, and provided several senior theses, Masters and Ph.D. Projects. The online learning program draws thousands per month. Visit: [http://www.rjd.miami.edu/." http://www.rjd.miami.edu/](http://www.rjd.miami.edu/." http://www.rjd.miami.edu/).
Later in the day, we hooked a hammerhead, Neil's favorite shark, and the source of Brendal's intense fascination.
Though it wasn't a large hammerhead, Neil made the decision to attach a $2,000 satellite tag to the fish's dorsal. Capt. Curt and Dr. Neil again, are in a unique niche that requires fishing, boating, carpentry and surgery skills.
"After years of taking from the marine environment, it's a good feeling to know that by working with Neil I get to give something back," Curt said.
The tagging mechanism includes a streamlined satellite tag coated with special environmentally friendly anti-fouling material. Titanium bolts and stainless steel lockers are used so that it stays attached to the shark without hindering their swimming ability. Neils' team can immediately follow that shark with an Iphone immediately. The most impressive migration story is that of a great hammerhead that swam from the middle Keys about 1,200 miles to the same latitude as Pennsylvania, in one month. It swam through a gauntlet of longlines to get there. "We need a national ocean policy that protects sharks and other highly migratory species throughout their range, and international collaboration on shark conservation," Neil said.
The crew performed this surgical feat and collected the other samples and data in three minutes flat.
Hammerheads in the Atlantic are International Union for Conservation of Nature's red list, which means they're endangered. The eye location on a hammerhead allows them to see 180 degrees as they sway their heads back and forth while swimming. They work like two, fisheye lenses, that are separate "torch beams" searching the depths.
You can sex a shark by seeing whether it has "claspers" like these. Most sharks reproduce by having intercourse, and the females carry pups through term and give live birth.
The team also set fish traps to sample the diversity of forage in the area. Chronic over-fishing of reef fish, which spend their juvenile life stages in grassy areas, may be reducing the diversity and supply of food. The loss of big sharks also has ripple down effects. Big sharks eat small sharks, and small sharks eat small fish. Remove the big sharks and the little ones become too abundant, and deplete the smaller fish. We only caught two common baitfish in the traps, pinfish and sand perch, which aren't commercially fished except for bait.
This "sand perch" is actually a type of wrasse common in seagrass meadows. Neil takes fin clips to analyze them for toxins. Toxins "bio-magnify" up the food chain, because bigger animals as you move up the chain must consume up to ten times more biomass to sustain growth and reproduction efforts. This technique is one way to monitor whether oil and dispersants from the Deepwater Horizon disaster have infiltrated the food chain, and ultimately threaten human health. So far the Keys and Florida Bay seem oil/dispersant free.
When you target sharks, rule number one is to practice responsible catch-and-release. Few sharks are very good eating. Some, like the hammerhead are inedible because their meat rots so quickly and because it contains high mercury levels. Many are in trouble due to intensive commercial and killing for sport, when fiberglass mounts look better and last longer than skin mounts that require you to kill the animal. Second, unless sight-casting with a fly rod, always use circle hooks. You'll rarely gut-hook a shark that way, since the hook almost always sticks in the corner of the mouth, as this thousand-year-old technology is designed to do. Third, don't bring a knife to gunfight. Tackle up, so you can whip the fish quickly, ensuring it the best possible chance for survival. Don't go under 100-pound-test. Finally, be careful. These fish get ornery near the gunnels. Leave the fish in the water to protect yourself, the boat and the fish. Long de-hookers or even bolt cutters can remove the hook. Otherwise, cut the line as close to the hook as is possible and safe.
Big smiles after a highly successful day of cooperative research and education ends with more data collected, and more tags deployed. You can go online and track the hammerhead we dubbed, "Sandy." Visit: http://www.rjd.miami.edu/learning-tools/follow-sharks/. Special thanks to the Keys Marine Lab, which hosted the expedition. And, for those interested in shark conservation, there's some good news for sharks and shark anglers. The state of Hawaii just banned the sale, trade or possession of shark fins. And, the Shark Conservation Act of 2009 (Senate Bill 850) looks like it will soon pass. It will close the loopholes that still allow shark finning, the practice of removing the shark's dorsal fin for sale and wasting the rest of the body. It amends the High Seas Driftnet Fishing Moratorium Protection Act to allow the U.S. to identify nations that do not have comparable shark conservation measures in place. Further, it grants U.S. authorities the ability to restrict imports of shark products from those countries. Interested in fishing the Keys, visit: www.fla-keys.com.