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Does the EPA Understand the Environment?

4/17/2015

Concerned citizens take it upon themselves to monitor the drum lines, often rescuing animals that would have otherwise died, such as this ray. In the video you can see how the hook has lacerated the ray's underside

Concerned citizens took it upon themselves to monitor the drum lines after realizing the government / Fisheries were doing an exceptionally poor job of monitoring. In this case, one of the doomed animals that was rescued was a large ray. In the video you can see how the hook has lacerated the underside of the ray even as it protrudes from the ray's mouth.

The application to continue the shark cull another three years was rejected by the Environmental Protection Authority in Western Australia. However, the imminent threat policy was. The EPA justified this decision claiming that the targeting of a few sharks was not likely to play a large impact on the environment. In this interview, scientists Malcolm Francis and Jessica Meeuwig explain how our lack of understanding of the reproductive nature of sharks, particularly white sharks, might prove the EPA's reasoning to be flawed. Jeff Hansen of Sea Shepherd contributes commentary on the Imminent Threat Policy.

Footage by Rohan Sibon and Skyler Thomas.
This is a scene from the director's cut of #GreatWhiteLies
greatwhitelies.com

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White Shark Jaws...Unhinged

4/9/2015

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The upper jaw of the white shark is not fused to the skull. Instead, the jaws are slung loosely beneath the skull, held in place by flexible connective tissue and braced by accessory cartilages. Special muscles pull the jaw forward and down, riding on grooves on the undersurface of the skull. This arrangement allows this shark to protrude its jaws outward from the head, extending the reach of its teeth and creating a partial vacuum that helps suck in prey. This comes into play when one considers the teeth. The teeth have broadly triangular blades with coarsely serrated edges. The upper teeth are broader and flatter than the lower teeth, which reflects their different roles during biting. The lower teeth stab into and hold secure a food item while the saw-like upper teeth gouge out a hunk of flesh as the detached jaw extends forward and crashed down to meet the teeth holding the target in place. This dental arrangement allows the white shark to feed on prey too large to swallow whole as well as scoop out calorie-rich blubber from whale carcasses.
The two photos (by #WSV cameraman MJ Billen) featured here show how a white shark's upper jaw can appear almost toothless until the jaw moves forward and down to reveal the impressive teeth waiting within (image 2).

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Mapping the White Shark Cafe...Again

4/1/2015

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"Strongly directional swimming" is my new favorite "scientific" term. Apparently sharks are heading in a direction while they swim and that was worth publishing another paper about the White Shark Cafe. Or maybe this is an example of "publish or perish" or an attempt to justify the use of SPOT tags. I know Bonfil has made strong contributions to white shark research over the years, but I'm not too impressed by this paper analyzing someone else's data. The first image is the map provided in Bonfil's paper and a link to the paper. Make your own conclusions of the significance of the new map to the old SAT tag maps. Next do a Google search for any conservation measures that have been put in place thanks to SPOT tags on white sharks. Leave your conclusions in the comments.

Link to full paper

This is an image of the map provided by Bonfil's analysis of one SPOT tagged white shark.

Below are articles, papers, and maps of the White Shark Cafe for white sharks traveling from the Farallones and from Guadalupe out to Hawaii and back without the use of SPOT tags.

link to article - Stanford Report, 2008, Jorgensen data

This graphic shows the route of a single tagged white shark as it swam from the Farallon Islands, off the central coast of California, to the mid-oceanic area known as the “White Shark Café” and then back.

Courtesy of TOPP

This shows very directional movement, yet no SPOT tags were required, just patience.

link to article - Mercury News, 2009, Jorgensen data

This graphic shows the routes of 6 specific white sharks. One appears to have bypassed the cafe and gone straight to Hawaii while all the others went to the Cafe
Courtesy of Stanford University

This article was particularly interesting because the acoustic tags revealed that white sharks actually do enter the San Francisco Bay, past the Golden Gate Bridge, for short times.

Again, no SPOT tags required.

link to article - Telegraph.UK, 2008, TOPP data

Now that's a very detailed map...that didn't requite SPOT tags.

Site fidelity of white sharks tagged along the central California coast during 2000–2007 revealed by PAT records. (A, B, C, D, E, and F) Fidelity is demonstrated by six individual tracks (yellow lines; based on five-point moving average of geolocations). Triangles indicate tag deployment locations and red circles indicate satellite tag popup endpoints (ARGOS transmissions) for white sharks returning back to central California shelf waters after offshore migrations. (G) Site fidelity of all satellite tagged white sharks (n = 68) to three core areas in the Northeast Pacific including the North American continental shelf waters, the waters surrounding the Hawaiian Island Archipelago, and the white shark “Cafe” in the eastern Pacific halfway between North America and Hawaii. Yellow circles represent position estimates from light- and SST-based geolocations (Teo et al. 2004a, 2004b), and red circles indicate satellite tag endpoint positions (ARGOS transmissions), respectively. From Jorgensen et al. ( 2010).

Link to full paper
Movement patterns for two out of 20 white sharks tracked from 1999 to 2005. Sharks 17-U (small circle) moved from the tagging location in California (arrow) to the offshore focal area and back to California where the tag popped up (large circle); white shark 18-F (small triangle) moved from California to Hawaii, where the tag stopped recording data (large triangle). Colors denote month. Pie diagram shows days of the year spent in four phases by shark 17-U

Link to full paper

Here are the tracks of 4 individual white sharks from Guadalupe Island to the White Shark Cafe and to Hawaii between 2000 and 2008.

Of particular interest is the fact that this data is based on pop-off SAT tags in a paper by Michael Domeier. I mention this because Domeier is an advocate of SPOT tagging despite his own evidence that it is unnecessary.

Domeier is best known for giving birth to OCEARCH by providing them with their first permit to go big game fishing for a protected species while getting big pay checks for being on a TV show. The world of white shark tagging has been in a downward spiral of garbage and ratings ever since. Thank you so much for your contribution, doc

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Does the EPA Understand the Environment?

White Shark Jaws...Unhinged

Mapping the White Shark Cafe...Again

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