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Monday, December 2, 2013

Threats To Sharks Threaten Entire Ecosystems

Inside Science Minds presents an ongoing series of guest columnists and personal perspectives presented by scientists, engineers, mathematicians, and others in the science community showcasing some of the most interesting ideas in science today.
(ISM) -- Throughout most of the world sharks are in trouble. Big trouble. In some areas, with adequate management, shark populations have stabilized, but likely at levels far below what they were decades ago. In the rest of the world, shark fishing continues to be a major threat to many species. Recent estimates suggest that around 100 million sharks are taken by fisheries every year
Because of their slow growth – sharks may take a decade or more to reach maturity – and low rate of reproduction – many species have fewer than a dozen young a year – this rate of catches is unsustainable. The decline of sharks will continue.
Why should we care? What will that mean for the oceans and even for fisheries targeting species other than sharks? We know from studies on land that when large predators are removed, entire ecosystems can be destabilized. That can be bad for animals and people. If similar things happen in the oceans, we not only need to think about halting declines of sharks, we will probably need to find ways to rebuild their numbers.
The attention that the Discovery Channel's Shark Week brings to these animals is great, but that attention needs to extend beyond the first week of August for these predators and the places they live to recover and eventually thrive.
For the past fifteen years, my colleagues and I have been trying to figure out how important tiger sharks are in the aptly named Shark Bay, Western Australia. Why travel halfway around the world? Quite simply, to study sharks in a place where their ecosystem is relatively untouched. Also, because Shark Bay features some of the world’s largest seagrass beds. Seagrass is important because it provides a habitat that supports populations of fish and shellfish that people rely on. It also helps to combat climate change by pulling carbon dioxide out of the atmosphere. By working in Shark Bay we can understand the role of sharks and what might happen to Shark Bay and its seagrass if tiger sharks were to disappear. It also lets us predict what might happen in other places where sharks have been overfished.
In Shark Bay, we have worked not only on sharks, but on their prey — including dolphins, sea turtles and sea cows — as well as the wider ecosystem. Our findings demonstrate that tiger sharks are critical to the Shark Bay ecosystem. But not in the way you might think. It turns out that the fear of sharks – by the sea cows and sea turtles that eat the seagrass – helps protect the seagrass from being over-grazed.  
Here is how it works: Tiger sharks like to hunt in shallow waters in the bay; a perfect place for seagrass to grow. To avoid becoming a shark snack, turtles and sea cows generally avoid these areas. The seagrass can grow into a lush habitat that provides shelter for small fish and shellfish that will grow up into species people want to catch. In areas that sharks don’t frequent, seagrass is heavily grazed and does not support big populations of fish and shellfish. That means that if we were to lose tiger sharks from the bay, the seagrass likely would be grazed down all over.
The loss of seagrass would be bad news for fish and fishermen – and maybe even for turtles and sea cows! It also could result in the loss of a large amount of carbon dioxide back into the atmosphere that would no longer be stored by seagrasses. There is evidence that the loss of sharks is hurting seagrass in some places. 
In Bermuda and the Indian Ocean, where shark populations have declined, increasing populations of sea turtles are causing entire seagrass beds to virtually disappear. And it isn’t just in seagrass ecosystems where sharks are important. Recent studies point to the possibility that healthy coral reefs need sharks, too.
Luckily, many countries have begun to recognize that sharks can draw tourists. The associated economic benefits of shark tourism can outpace the income from fishing for sharks. There also has been a growing realization that if we don’t slow down shark fisheries, they will disappear. This has led some countries to adopt fishing quotas aimed at keeping sharks at sustainable population levels. 
Other countries have gone further. Shark sanctuaries – where they are protected from being fished - have been declared throughout the waters of a number of countries around the world. This kind of precautionary approach is vital to protecting and restoring shark populations while scientists work to learn more about their potentially critical role in coral reef and other marine ecosystems. 

Tiny fish gives big evolutionary insight

The defence secrets of a tiny, leaping, amphibious fish, unveiled by NSW scientists, may give an insight into how life survived the transition from aquatic to terrestrial habitats.

The Pacific leaping Blenny grows to only eight centiUniversity of NSW first compared the colours of five Blenny populations with the rocks they lived on.
After discovering the colours were almost identical they modelled Blenny lookalikes out of plasticine and placed them in the habitat.
Dr Ord said the models were collected after several days and the incidence of attacks from birds, lizards and crabs recorded.
"We found the models on the sand were attacked far more frequently than those on the rocks," he said in a statement.
"This means the fish are uniquely camouflaged to their rocky environments and this helps them avoid being eaten by land predators."
They also found closely related fish had similar colouration, meaning the Blenny's ancestors were probably rock coloured when they first moved out of the water.
"These species provide an evolutionary snapshot of each stage of the land invasion by fish," said Dr Ord.metres and spends its time leaping from rock to rock, defending territory and feeding on the tropical island of Guam.

Stray animals used as shark bait: Stop the horrific use of stray animals as shark bait

On the French-controlled island of Reunion, stray dogs and cats, both LIVE and dead, are being used as shark bait. Large hooks are plunged into their noses and/or paws, and they are then tossed into the ocean to draw sharks. Please sign this petition to stop this barbaric practice!

http://www.change.org/petitions/stray-animals-used-as-shark-bait-stop-the-horrific-use-of-stray-animals-as-shark-bait

Ride the Peace Train, or Peace Reef - Be a part of the project! Plant a reef!

$85 per person includes tanks and weights.  Project is to plant a reef in the shape of a peace sign that can be seen from outer space.  This will help the environment by making it educational and creating a permitted live rock farm that is also a reef.  A sustainable eco friendly way to help the environment in the Florida Keys, the Peace Reef sits in the Atlantic Ocean approximately 2.5 miles offshore of Islamorada, Florida in twenty-feet of water. The site for this project is leased from the State of Florida and is located in protected seas. One of the purposes of the Peace Reef Project is to call attention to and inform the public about the benefits of effectively reconstructing natural coral reefs around the globe. Since only natural limestone rock is used to construct the Peace Reef it will serve as a model of how to cost effectively rebuild natural reefs while maximizing the benefits to the environment using this natural approach. This is literally how many natural reefs have formed throughout the ocean's history. Limestone rock and coral skeletons are broken off of existing reefs and are dispersed by storms and currents, sometimes together in small groups. Gradually new life colonizes these congregations of rocks and new reefs are born and grow.
Dive the "Peace Reef"All aboard... the Peace Reef meetup 
Someone wants to share the dive love.  Peter Wolfson has the most amazing passion to build a beautiful reef in the shape of a peace sign so very large that it can be seen from outer space!  Talk about a revolution!  Reefs are the foundation of the ocean and they help sharks too.  Success is happening and we wanna be a part of it as usual.  If you like me want someone not just to tell you what NOT to do, but instead tell you WHAT TO DO!  This is what to do!

Conservation divers, join me on an exciting 'Peace Train, or cough, boat trip to say proudly you put down some of the live rock on "Peace Reef"  You can help Peter build it!  Together we can make a reef!  

3/1/14 is the date and due to the drive it will be an afternoon dive.  
We need more boats too.  If you have one and wanna bring it to carry some of the buckets of limestone that would be great.  If you wanna help with out being a diver we need you to lower the buckets of stone via lines too or snorkel and help.  It is all hands on deck aboard the peace train!!  The estimated costs are $85 per diver including tanks and weights for the dive boat but we will have final costs soon.  You will need to bring a lift bag if you have one.  If not i can get one wholesale for you.  We will also be doing reef field surveys during the dives and taking photographs of the site for historical record and cataloging the existing life on the reef now at reef.org so sign up for a free reef.org membership if you have not already.  Expect a great time!  Here is a video to learn more about it.
See videos explaining the project here: http://www.peacereef.com/new-page/
Can't make it?  You can still help with Peter's program here:  

Coral Restoration Dive CLASS! $130 - All ages and levels - Class & 2 Tank Dive!

January 11, 2014- CRF DIVE
Class first at Coral Restoration Foundation at 8:30am
5 Seagate Blvd., Key Largo, FL 33037
Then lunch at Pilot House nearby and then...
All divers to present themselves at the dock by 12:30 PM for the dive.
13 Seagate BLVD
Key Largo, FL 33037
The parking lot for our boat is located in the chain-linked area directly facing the Coral Restoration Foundation building.
Our boat is behind the CRF building, to the right.
*Divers who require equipment for the dive will have to come to our shop (99696 Overseas Hwy, Key Largo) for payment prior to the dive. No exceptions.
Divers MUST have their diver release forms completed, and have their C-card on hand. No exceptions.
Release forms here:
_____
Conservation Club is doing a Coral Restoration Training, then lunch (included) and then in the afternoon a 2 Tank Dive on the largest Coral Nursery in the world!
The price includes the whole day of fun and coral restoration.
If you wanted to learn to save coral reefs, frag and propagate coral then this dive is for you! Great easy dive in Key Largo 9/8/13. Price includes, lunch, training, boat trip, dives, weights tanks, and coral restoration class and actual hands on experience.  You will learn all about coral and building reefs, then you will learn how to hang them to grow fast, and on the dive actually plant a few coral cuttings into the nursery, learn to maintain the nursery and then on your second dive take healthy cuttings and plant those on the reef.

You must have EXCELLENT Bouyancy Control for these dives!~
Join your fellow conservation club members aboard Keys Diver II for a full day of fun and of diving and kick off the new year by actually doing something to change your environment.
You'll dive and see some of the most beautiful reefs in the world now being healed, but, more importantly you will be doing your part to ensure they are still here, thriving for generations to come. Make a difference this year!
Do the Coral Restoration Dive!
We will learn from Ken Nedimeyer and the Coral Restoration crew just what streses corals and causes a decline in our reefs - cold weather, acidification, excessive CO2 and, yes, divers!
Prepping the corals and cleaning them.

Measuring and numbering Staghorns.

But, you can make a difference this September. Visit the largest underwater coral nursery in the world. Learn about Staghorn and Elkhorn corals. Care for them, then transplant them to America's only living coral reef.
Corals growing on lines in the nursery seem to be less susceptible to disease this way. Ken has now developed 'tree nurseries' to grow the corals with even more success.  It is amazing to see acres of underwater coral trees.. it is like Christmas all over again~

Morning Session
The morning will be an introduction to CORAL RESTORATION FOUNDATION- who we are, what we do, our nurseries, basic coral info and why the decline of staghorn and elkhorn, then a briefing on what the group will do that afternoon in the nursery.
Lunch (included) at the Pilot House Glass Bottom Bar and Restaurant. Keys Diver II is docked at Pilot House Marina. (Coral Restoration Foundation has the Pilot House on the right and the boat on the left so you can walk over and walk back to the dock to board the boat.. no need to even move your car).  Parking is across the street and is free.
Afternoon Session
Two tank dive on the nursery.
Two tank dive, transplanting corals to the reefs off Key Largo. Most likely location is the Tavenier grounding area.
Only $130 per diver .
Price includes:
$80 FOR THE DIVES AND $50 FOR THE CORAL RESTORATION FOUNDATION morning of Coral Restoration Classes, Afternoon of 2 tank dive to the nursery and reef, tanks, weights, and your lunch is all included at the Pilot House Glass Bottom Bar.
Part of the required charge of $130 includes a donation of $50 directly payable to the Coral Restoration Foundation in your name OVER THE $80 DIVE FEE FOR A TOTAL OF $130.
If you need a room, contact the Key Largo Bayside Inn, just blocks from the dive boat, and on the Florida Bay with stunning sunsets. 1-866-365-9867
Payment due in full at time of booking.
No refunds 7 days prior to event unless due to
weather related incident or captain cancels the dive, then the dive fees will be refunded.
Full gear rental just $25, mask, fins, snorkel, reg, octo, BCD, computer.
NOTE: Divers must be certified and bring their C cards with them and required paperwork which can be found here: http://files.meetup.com/2116971/General%20Diver%20Info%20%26%20Release.pdf

Please complete paperwork in advance.

Sunday Species Snapshot: Daggernose Shark

These small sharks pose no threats to humans. The opposite, however, cannot be said.
Species name: Daggernose shark (Isogomphodon oxyrhynchus). Notable for their flattened snouts and relatively large fins, these small (1.5 meter) sharks are the only members of their genus.
Where found: The shallow coastal waters off of northeastern South America, where they predate upon schools of small fish.
IUCN Red List status: Critically endangered
Major threat: Overfishing, although most fishermen aren’t targeting these sharks directly. Instead the sharks are caught in nets intended for other species. Two studies conducted in one Brazilian state in the 1990s found that daggernose sharks comprised as much as 10 percent of regional fish catches. The rate of fishing combined with the shark’s slow reproductive rate has caused dramatic population declines. A 2002 study found that populations had dropped more than 90 percent over the previous decade.
Notable conservation programs: None that I could find. Heck, I couldn’t even locate a photo of this species or any recent research about it. This critically endangered species could definitely use some targeted aid.

Hark! A Shark!: All About Sharks (Cat in the Hat's Learning Library)

In this latest installment of the Cat in the Hat's Learning Library, the Cat introduces beginning readers to all kinds of sharks! From the smallest (the dwarf lantern) to the largest (the whale shark), the most notorius (the great white) to the most obscure (the goblin), the Cat explains why sharks have lots of teeth but no bones; how their tough skin helps them swim fast and stay clean (inspiring scientists--and bathing suit manufacturers!); how pores along the sides of their bodies help them sense prey; that they have more to fear from us than we do from them, and much, much more! Perfect for shark and Cat (in the Hat) fanciers, fans of the new PBS Kids preschool science show The Cat in the Hat Knows a Lot About That! will sink their teeth into this new addition to the series! 

Get it here.. http://www.amazon.com/gp/product/0375870733/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0375870733&linkCode=as2&tag=besshavid-20