I particularly like that they go into enough detail to lay out options for incorporating predation into fisheries. Personally, I’m a big fan of the “second fleet” option, in which predators are counted as another source of fishing mortality (and some of my favorite papers are cited in support of it). It does require the most effort, but provides the most accurate estimations of predation mortality (and justifies funding for diet studies? Please?). Multi-species models are ideal, and really the only way to conclusively prove that trophic cascades are actually happening. Precautionary buffers, in my opinion, should really follow thorough diet studies, but are certainly another important aspect of ecosystem-based management.
It’s neat to finally see this subject getting some attention. Here’s hoping the word continues to get out about the importance of shark puke.
When you work on the water long enough, you encounter some unique situations. Whether it’s getting stranded during field work, surviving massive seasickness, having your equipment attacked by hostile sea life, or just seeing something unusual, these anecdotes are an important part of what makes marine science fun (sometimes moreso in hindsight). That’s why I’m creating a new category for posts here called “Fish Tales,” where we can share these stories. To start with, here is a literal fishing story.
While I was down in Morehead City for some field work (post on that coming soon), I got the chance to do a little fishing with fellow Southern Fried writers Andrew and Amy and check on potential sites for shark sampling this summer. I’d wanted to test out a new fishing rod set up for sharks and large fish, and had rigged up a wire leader with a size 12/0 circle hook. While casting, it became very clear that I hadn’t properly attached the leader to the swivel when I pulled back an empty swivel where the leader had been. Frustrating, but I’m practically required to lose gear every time I fish, so I rigged up a second wire leader with a J-hook that was on hand.
Circle hooks are used by recreational and commercial hook-and-line fisheries (and many longliners) to reduce hooking mortality in large fishes, sharks, and bycatch animals like sea turtles. The idea is that the hook more or less works by itself without being set like a J-hook. The shape of the hook prevents swallowing and encourages hooking in the corner of the mouth, where it’s less likely to do serious damage.
I’ve written in the past about why shark fin bans might not be the best tool for the conservation and management of sharks. Though specific details vary, these so-called “blanket bans” typically make it illegal for anyone to buy, sell, or possess shark fins regardless of the source *. Additionally, to date most of these fin bans have taken place in a few U.S. states and Canadian towns. If the goal of these state-level fin bans is to reduce the supply of fins to the global market, proponents should consider that according to TRAFFIC, more than 95% of the supply of shark products comes from countries outside of the U.S. and Canada. Even if every U.S. state passed a fin ban, it would have a negligible direct impact on global supply. Additionally, the United States has some of the most sustainably managed shark fisheries in the world (hammerhead sharks and a few others are an exception). We want other countries to emulate out management practices, not to remove our management practices from the global marketplace.
If the goal of these local fin bans is to reduce global demand, proponents should consider that the overwhelming majority of the demand for shark fin soup is in China and Southeast Asia, where passing such bans will pose a significant challenge. Some proponents of fin bans say (after the negligible impact on supply and demand is pointed out) that fin bans help with ”raising awareness of the problem of overfishing of sharks”. While these fin bans do result in (relatively) positive media coverage for shark conservation, “raising awareness” is not the publicly stated goal of these bans. If your goal is to educate people about a problem, educate people about the problem.
Recently, the United States National Marine Fisheries Service (which, once again, manages some of the most sustainable shark fisheries on Earth) has started to officially speak out against state level fin bans.
A great hammerhead shark swims by a Project AWARE “Extinction is NOT an Option” sign, Bimini, Bahamas. Photo credit: Neil Hammerschlag
The Endangered Species Act is one of the strongest conservation laws on the planet, and to date, no shark has ever been given ESA protections. In recent weeks, however, the National Marine Fisheries Service has responded to a series of NGO petitions requesting ESA protections for two species of hammerhead sharks. NMFS proposes to list 2 “distinct” population segments” (DPS) of scalloped hammerhead sharks as endangered and 2 as threatened, with 2 DPS’s listed as “not warranted”. The response to the great hammerhead petition is not as developed (the petition itself is more recent), but notes that “the petitioned action may be warranted”.
I strongly believe that both of these species of hammerhead sharks need and qualify for Endangered Species Act protections. If you agree, I encourage you to submit an official public comment in support of listing both under the ESA following the instructions below. Failure to follow all instructions to the letter will result in your comment not being considered. Commenting on this blog post does not count as submitting a public comment, and neither does commenting on a Facebook post about this blog post. Online petitions will not be considered. This process is open to the public, but requires that we follow basic instructions.
To submit a public comment in support of great hammerhead ESA listings, click on the “comment now” button on this page and fill in the required information. To submit a public comment in support of scalloped hammerhead ESA listings, click on the “comment now” button on this page and fill in all the required information. You can also submit written comments via the mail to “Office of Protected Resources,NMFS, 1315 East-West Highway, Silver Spring, MD 20910 or by fax to 301-713-4060 attn: Maggie Miller. Please note that if you submit a comment by mail or fax, you need to include code NOAA-NMFS-2013-0046 for great hammerheads and code NOAA-NMFS-2011-0261 for scalloped hammerheads.
To help craft your public comment, I’ve written a list of 10 reasons why these sharks qualify for Endangered Species Act protections. Please do not just quote this post word-for-word, if you do then your comment will be considered a “form letter” and not an individual comment.
It’s the final cup in our series. Posting these images has been a fun way to reminisce about our adventures in the Cayman Abyss and hopefully give you a small glimpse into the more whimsical side of deep-sea research. To finish of the series, here is my favorite cup:
Evolution is the most creative force on the planet. Everywhere we look, we find species with novel and phenomenal adaptations that put their comic book brethren to shame. In no ecosystem is this more apparent than in the vast and unfathomable ocean. Marine species, especially those in the deep sea, have evolved to survive in a environment that is completely alien to us. Several months ago, I unveiled “Five organisms with real super powers that rival their comic book counterparts“, but that was just the beginning. Without further adieu, I give you 5 more marine organisms that put their superhero counterparts to shame (and one bonus critter).
In the deep sea, eyes are not among the most useful sense organs. While many deep-sea species have extremely reduced eyes, some have abandoned these organs entirely.Rimicaris exoculata is a shrimp endemic to deep-sea hydrothermal vents in the mid-Atlantic that is completely eyeless. Its carapace is smooth, without even a hint of reduced, vestigial eyes. This, unfortunately, is a problem because Rimicaris exoculata is a farmer. The blind shrimp grows bacteria in its gill chamber, bacteria that can convert the chemical-rich hydrothermal vent fluid into food for the shrimp.
For lack of a more descriptive adjective, hydrothermal vents are hot. Some can exceed 400°C. Rimicaris exoculata needs to get close to this hot vent fluid to feed its crop of bacteria, but not so close as to become a hydrothermal hors d’oeuvre. And so, the blind shrimp evolved a completely new light-sensitive organ mounted on the top of its carapace–the rhodopsin-rich dorsal eyespot.
The dorsal eyespot of Rimicaris exoculata doesn’t “see” in the normal sense, there is still almost no light in the deep sea. Rather, this shrimp is adapted to detect the black body radiation emitted by the hydrothermal vent. For Rimicaris exoculata, the deep sea glows with the light of super-heated hydrothermal fluid, allowing it to both find food for its bacterial crop and avoid getting cooked itself.
It should be no surprise that Rimicaris exoculata is undoubtedly the favorite deep sea organism of another blind champion with super senses–Daredevil.