Category Archives: Sea Creatures

Bigfoot, the Kraken and night parrots: searching for the mythical or mysterious

Euan Ritchie, Deakin University

It’s remarkable how little we know about Earth. How many species do we share this planet with? We don’t know, but estimates vary from millions to a trillion. In some respects we know more about the Moon, Mars and Venus than we do about the ocean’s depths and the vast sea floors. The Conversation

But humans are inquisitive creatures, and we’re driven to explore. Chasing mythical or mysterious animals grabs media headlines and spurs debates, but it can also lead to remarkable discoveries.

The recent photographing of a live night parrot in Western Australia brought much joy. These enigmatic nocturnal birds have been only sporadically sighted over decades.

Another Australian species that inspires dedicated searchers is the Tasmanian tiger, or thylacine. A new hunt is under way, not in Tasmania but in Queensland’s vast wilderness region of Cape York.

This is the first photograph of a live night parrot, taken in Western Australia in March 2017.
Bruce Greatwitch

Other plans are afoot to search for the long-beaked echidna in Western Australia’s Kimberley region.

In the case of the thylacine, old accounts from the region that sound very much like descriptions of the species raise the prospect that perhaps Cape York isn’t such a bad place to look after all.

But in reality, and tragically, it’s very unlikely that either of these species still survives in Australia. For some species there is scientific research that estimates just how improbable such an event would be; in the case of thylacines, one model suggests the odds are 1 in 1.6 trillion.

Chasing myths

The study and pursuit of “hidden” animals, thought to be extinct or fictitious, is often called cryptozoology. The word itself invites scorn – notorious examples include the search for Bigfoot, the Loch Ness Monster or Victoria’s legendary black panthers.

The search for Bigfoot is an extreme case of cryptozoology.

Granted, it’s probably apt to describe those searches as wild goose chases, but we must also acknowledge that genuine species – often quite sizeable ones – have been discovered.

Remarkable discoveries of animals thought to be fantasies or long extinct include giant squid, mountain gorillas, okapi, Komodo dragons and coelacanths.

In some cases, like the giant squid, these animals have been dismissed as legends. The reclusive oarfish, for example, are thought to be the inspiration for centuries of stories about sea serpents.

Oarfish can grow up to 8 metres long and swim vertically through the water. Commonly inhabiting the deep ocean, they occasionally come to shallow water for unknown reasons.
AAP Image/ Coastal Otago District Office

Technology to the rescue

Finding rare and cryptic species is self-evidently challenging, but rapid advances in technology open up amazing possibilities. Camera traps now provide us with regular selfies of once highly elusive snow leopards, and could equally be used with other difficult-to-find animals.

Candid camera, snow leopards in the Himalayas.

Environmental DNA is allowing us to detect species otherwise difficult to observe. Animal DNA found in the blood of leeches has uncovered rare and endangered mammals, meaning these and other much maligned blood-sucking parasites could be powerful biodiversity survey tools.

Acoustic recording devices can be left in areas for extended time periods, allowing us to eavesdrop on ecosystems and look out for sounds that might indicate otherwise hidden biological treasures. And coupling drones with thermal sensors and high resolution cameras means we can now take an eagle eye to remote and challenging environments.

Drones are opening up amazing possibilities for biological survey and wildlife conservation.

The benefits of exploration and lessons learned

It’s easy to criticise the pursuit of the unlikely, but “miracles” can and do occur, sometimes on our doorstep. The discovery of the ancient Wollemi pine is a case in point. Even if we don’t find what we’re after, we may still benefit from what we learn along the way.

I’ve often wondered how many more species might be revealed to us if scientists invested more time in carefully listening to, recording and following up on the knowledge of Indigenous, farming, and other communities who have long and intimate associations with the land and sea.

Such an approach, combined with the deployment of new technologies, could create a boom of biological discovery.

Euan Ritchie, Senior Lecturer in Ecology, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University

Stranded Sea Lion Found Wandering San Francisco

A small brown sea lion who goes by the name “Rubbish” decided today to leave behind the ocean and instead tour the coastal city of San Francisco on foot, or rather flipper, on Thursday morning. Someone sighted the friendly creature near San Fran’s Marina District at about 7 a.m. and decided to call it in. Laura Sherr, a spokeswoman from the Marine Mammal Center of Sausalito, confirmed that the sea lion was brought to the center for a routine check up and care after he had been humanely captured.

Marine mammal rescuers are concerned that events like this could become more commonplace, due to global warming heating up the Pacific Ocean. A recent study conducted by the National Oceanic and Atmospheric Administration, suggests that this little confused sea lion is hardly alone. Rubbish is just one of at least 1,800 California sea lion pups who had been found stranded alongside the west coast this year. This is probably the result of drastic increases of the ocean’s temperature coupled with a continuously diminishing supply of food.

“In the first four months of 2015, we have rescued more animals than we rescued during the entirety of 2014,” said the center’s chief veterinarian Dr. Shawn Johnson. “What’s scary is that we don’t know when this will end. This could be the new normal–a changed environment that we’re dealing with now.”

Johnson also revealed that this also was not the first time the rescue center had taken in Rubbish. He was named by and cared for at the center back in February, shortly following his rescue from the Santa Barbara Marine Mammal Center and was afterwards transferred to the Marine Mammal Center, where he was cared for as an eight-month-old pup. At the time, Rubbish weighed only 30 pounds, and was suffering from pneumonia as well as malnutrition. Shortly afterwards, he put on an additional 17 pounds and after being deemed healthy, the caretakers set him loose at Point Reyes National Seashore on March 23.

Johnson believes that if the warming of our oceans continues to worsen, these situations will most likely persist. He listed three of the primary stressors in the marine environment: overfishing, pollution, as well as global warming.

“We know everything is connected—a change in the winds is leading to thousands of sea lions stranding on the beach,” he said. “It’s all the more reason we should be paying close attention to the fate of sea lions, a top predator in the ocean.”

James Sullivan
James Sullivan is the assistant editor of Brain World Magazine and a contributor to Truth Is Cool and OMNI Reboot. He can usually be found on TVTropes or RationalWiki when not exploiting life and science stories for another blog article.

New Study: Octopus has plenty brains, no rhythm

While the movement of octopuses could be described as a simple elegance, it may shock you to learn that in fact, they really have no underlying rhythm, according to the latest research.

Each of the octopus’s eight arms is soft, flexible and muscular, almost pure muscle but capable of acting like it contains an infinite number of joints, according to the study’s lead author, Guy Levy, who is a postdoctoral researcher of neurobiology at the Hebrew University in Jerusalem. Until now, however, scientists have long sought to understand exactly how these marine animals are able to flawlessly coordinate their movement with a total of eight long and complex tentacles.

What also makes these animals so endearing for study is their incredible brain power – as they have long been reputed to have the ability to remember. Their brains contain half a billion neurons, compared to most mollusks who have only 20,000, giving them the biggest brains of all invertebrates. Equally, if not more astounding, is their incredible talent for mimicry – imitating the shape and color of a number of marine creatures.

In order to further understand more about how these brainy creatures move so gracefully, either swimming, crawling the sea floor, or even creeping stealthily on land, the researchers watched a number of high definition videos, frame by frame, which showed octopuses crawling around in large water-filled tanks.

“The octopus, as usual, surprised us,” Levy told Live Science in a recent interview. “We found very unique things that we don’t see in other animals.”

Octopuses possess a rather unique strategy in order to coordinate their arms when they crawl, the researchers discovered. The cephalopods are in fact, bilateral symmetric, which seems like a mouthful, but simply means that both their left and right sides are perfect mirror images of each other. The majority of bilateral-symmetric animals are facing forward as they move, with one of the few exceptions being the blue crab, which typically moves sideways. They may even possess the ability to play, puffing around the toy placed in their tanks with jets of water – something that not many other invertebrates do.

But octopuses have an advantage: They are able to crawl in any direction that is relative to the orientation of their body, according to the researchers. In other words, unlike you or me, octopuses do not have to maneuver their entire bodies in order to change direction. All it takes is one of the octopus’s arms to push the entire animal from ofs a surface and then propel it any which way, Levy said.

“It simply chooses other arms to push the body, and the direction is changed automatically,” he added.

The scientists also learned that the octopus moves by way of shortening and elongating its arms, an action that results in a pushing thrust in the water. The animal does not have to actually bend or pull on any of its arms, something that makes matters a bit simpler for the giant mollusk, according to Levy.

“It only has to decide which arms to use, and not how to use them,” he said. “It’s a very simple solution to a very complicated problem.”

However, after they had witnessed hours of octopuses moving on video, the researchers concluded that the octopus has no discernible rhythm. While most animals maintain a type of rhythm as they move, for example, people that move their legs in a left-right-left pattern, so far the octopus has no predictable rhythm in the coordination of its limbs, the researchers said.

“So, either there is no pattern, or it’s too complicated to identify with the techniques that we used,” Levy said.

The researchers did observe patterns of movement in their individual arms, which would conversely shorten and elongate, but there was no pattern apparent whenever the scientists observed all eight arms at once, Levy added.

It is likely that the octopuses acquired their unusual form of movement because, unlike their clam cousins, they do not contain protective outer shells to guard against predators, the researchers said. Unsurprisingly, the octopus is suspected to have an ancestor somewhat reminiscent of a snail, with one muscular foot that in time evolved into eight long and slender arms, which gave its descendants a great deal of flexibility. Octopuses gradually developed excellent vision, along with a large brain and also camouflage capabilities, traits that made them into adept hunters.

This means that octopuses would also require an effective way to travel.

According to the latest research, “The [octopus’s] strategy is simple enough, and it has a small number of parameters, and this is how it succeeds,” Levy said.

The results are a prime example of a concept known as “embodied organization.” For many years, researchers believed that these motor-controlled strategies were designed in order to suit the body. This concept of embodied organization, however, implicates that both motor control and the anatomy both evolve together, and they occur out of a response to the environmental pressures which are capable of influencing both, said the researchers in their paper.

The scientists are planning to use their findings in order to help engineers develop soft, easily manipulated robotic arms, Levy said. Along with the study’s senior author, Binyamin Hochner, a professor at the Hebrew University of Jerusalem, Levy hopes to further continue study on the octopus. The team has already discovered the reason why these creatures don’t inadvertently tie themselves up in knots, or tie up each other, which seems like a likely hazard due to the number of their limbs. The next phase of their plan is to uncover those neural circuits that are responsible for the octopus’ ability in coordinated crawling, Levy said, how they use their muscular tentacles for agile movement along the ocean floor.

These findings have been published online today (April 16) in the Cell Press journal Current Biology.

James Sullivan
James Sullivan is the assistant editor of Brain World Magazine and a contributor to Truth Is Cool and OMNI Reboot. He can usually be found on TVTropes or RationalWiki when not exploiting life and science stories for another blog article.

Saving our scallops: Arran reserve reveals marine protection works

Last summer, on the Isle of Arran, off the west coast of Scotland, we watched an excited young lad walking down to the water’s edge, fishing rod in hand. Sadly, his chances of catching anything were slim to remote.

Once plentiful stocks of cod, haddock and plaice have almost completely collapsed in the Firth of Clyde, the area of sea in which Arran sits, following a century of poor fisheries management.

Nowadays more than 99% of the commercial fisheries landings there are not for fish, but for shellfish such as prawns and scallops, which don’t take a bait.

Motivated by this dramatic change in their local marine environment, two Arran residents, Howard Wood and Don McNeish, formed the Community of Arran Seabed Trust back in 1995. They quickly seized on the idea of using marine reserves – areas of sea where fishing and other extractive uses are restricted – as a way to bring back the marine life they had previously enjoyed as scuba divers.

Small island, big marine protection.

Reserves had been used to great success in New Zealand and the Philippines, where the benefits appeared to have spilled over to the areas open to fishing. However marine reserves were non-existent in the UK at the time.

Finally, after over a decade of campaigning and building community and scientific support they got their reserve in Lamlash Bay in October 2008. It was small (only 2.67 km2 in area) but significant, being the first and still the only fully protected marine reserve in Scotland.

We’ve looked at the Arran reserve in our research. Our findings, published this year in the journals Marine Biology and Marine Environmental Research indicate marine life is starting to flourish once again.

Complex seabed habitats formed by seaweeds and other plant-like creatures are recovering. These in turn act as a magnet for juvenile scallops, cod and other tasty species.

Adult scallops are benefiting too, growing in size and reproductive capacity. High levels of breeding within the reserve are likely to be seeding surrounding fishing grounds.

Marine protection is growing

Marine reserves, such as that on Arran, are the most protected form of Marine Protected Area (MPA). Due to their perceived benefits for both conservation and fisheries, the use of MPAs has grown spectacularly over the past two decades. They now cover 2.8% of the world’s oceans, and the 2010 Convention on Biological Diversity set an ambitious target for this to grow to at least 10% by 2020. Both the UK and Scottish governments are rolling out further MPAs.

Fish-friendly Lamlash Bay.
User:Colin, CC BY-SA

There are strong arguments for the conservation value of MPAs. Clearly, if you protect ecosystems from activities which damage them, you expect benefits. Indeed, global analyses consistently find greater biodiversity and species size and abundance inside MPAs.

Certain habitats such as coral reefs and seagrass are highly sensitive to any kind of human disturbance, and protecting these areas should be a no-brainer given their ecological importance. Atlantic cod, for instance, rely on seagrass for shelter while they’re still growing.

However, the added restrictions these MPAs might put on fisheries has been met with strong resistance. In response to this lobbying pressure, it appears likely that UK governments will allow fishing to continue in the majority of the MPAs.

While low impact fisheries such as creeling and line fishing may be compatible with the conservation features in some MPAs, in many cases the most damaging types of fishing such as scallop dredging will be allowed to continue.

There are also no plans for any further highly protected MPAs, such as the one at Arran, to be established. Surely this is a wasted opportunity. Perhaps if the fishing industry could be convinced such MPAs would actually benefit fisheries, they would be met with less resistance.

Proving that highly protected MPAs benefit fisheries is difficult, but recent advances in genetics have conclusively demonstrated that disproportionately high amounts of young fish can be exported from marine reserves to neighbouring fishing grounds on tropical coral reefs.

Some scientists claim there is little evidence for them working in the cool temperate seas around the UK. But the Arran marine reserve story adds to the benefits that MPAs have provided to scallops around the Isle of Man and in Lyme Bay, and to lobsters around Lundy Island. Furthermore, recent modelling of the English Channel marine ecosystem concluded that highly protected MPAs were the best bet for both fisheries and conservation.

Crucially, the key to the success of the few MPAs in the UK to date has not just been getting the science right, but involving and getting support from the local community and fishing industries. Zoning arrangements divvying up the Clyde between fishermen and fish replenishment areas have just been proposed. This surely has to be the way forward.

The Conversation

This article was originally published on The Conversation.
Read the original article.

Shark attacks are so unlikely, but so fascinating

Sharks are incredibly unlikely to bite you. They’re even less likely to kill you. However, we remain fascinated with their ability – and occasional proclivity – to do just that. With so many things more likely to harm us, why do we pay such rapt attention when sharks make headlines?

As a shark researcher and curator of the International Shark Attack File (ISAF), it’s a question I think about each spring when I prepare my annual report of shark-attack statistics. This year we had some good news: In 2014 fatalities were down worldwide, as were attacks. In the US, attacks were up only slightly from 47 last year to 52, with most of those being minor incidents that are more like dog bites than something out of Jaws.

There wasn’t a single fatality in the entire country last year and only three worldwide. In the past decade, the US has averaged less than one per year. To put that into perspective, more people die from drowning every day in this country than were killed by sharks in ten years. In 2013, more people in the U.S. died from encounters with nonvenomous insects, and a lot more – 62 – were killed by hornets, wasps and bees, according to the Centers for Disease Control and Prevention’s Underlying Cause of Death database.

When you enter the ocean, you’re on their turf.
Alex Proimos, CC BY-NC

We’re in their aquatic territory more now

When you think of how much time we spend in the water, it’s amazing how innocuous shark and human interaction is. When the ISAF began in the 1950s, scientists were concerned primarily with shark attacks after ships and aircraft went down at sea.

A lot has changed since then. There are a lot more of us on earth today than there were back then and there will be even more tomorrow. Aquatic recreation has never been more popular. More people are kayaking, surfing, diving and paddleboarding.

More time in the water means more time to interface with sharks.
Stefan Schmitz, CC BY-ND

It’s partly a generational change. When my parents took a young me to the beach, my mother would lie on the sand and work on her suntan, never going in the water. My dad might have gone in once a day to cool off. Nowadays, if I’m at the beach, I might be boogie boarding or skin diving. Most of us are spending a lot more hours in the water than did our parents and our activities are inadvertently provocative. That creates ample opportunities for sharks and humans to get together.

Numbers may go up, but we’re learning

That’s why, even though fatalities are rare, we can expect to see an increase in the number – but not rate – of attacks. There aren’t a lot of things in science that I am willing to predict with certainty, but I am confident that in the second decade of this century we will see more attacks than in the first. That said, attacks are not rising as fast as we might suppose they would because we’re doing a better job of heeding beach safety and people are more shark-savvy than they were a decade ago. We’re starting to understand how to avoid sharks.

At the ISAF, we investigate every reported shark attack. Some are reported by hospitals, some by volunteers and scientists around the world. Others we find out about through traditional or social media.

In each case, through investigation we confirm that the guilty party was actually a shark. (You’d be surprised how many people who say they were bitten by a shark were bitten by something else, or not bitten at all.) We analyze the bite, which tells us the size of the shark, and sometimes the species. The ecological and behavioral circumstances surrounding the incident – from both the human and shark perspectives – give clues as to why the interaction occurred.

A little knowledge goes a long way.
Andreas, CC BY-NC-ND

Tracking helps with prevention

There’s practical benefit to tracking these attacks. By creating a rating system – the Shark-Induced Trauma Scale – we’re helping physicians create treatment plans based on the severity of a bite. And we can advise officials in areas that are seeing a spike in shark attacks on how to reduce risk.

Education and outreach are a big part of what we do. We tell people not to swim at dusk and dawn, when sharks are most active, and definitely not at night. (That midnight swim might be romantic, but it could be your last.) We know that you should avoid swimming where people are fishing, or where you can see fish schooling or seabirds feeding, which could mean sharks are feeding, too. We also advise against wearing bright, shiny jewelry into the water, which sharks can confuse for the flashing of fish scales.

I don’t want to bite you.
Travelbag Ltd, CC BY

People need to understand more fully that when we enter the sea, it’s a wilderness experience. We’re eco-tourists and are not owed the right to be 100% safe. That’s what fascinates us about sharks: There’s an innate concern in our psyches about not wanting to get eaten. Almost every other animal on earth has to worry about getting eaten night and day. As humans, we rarely have that concern. People hold sharks in awe as one of the rare species that reminds us we’re still potentially part of a food chain.

You’re much more likely to be injured or die during your evening run than in a shark attack, but don’t expect to turn on the Discovery Channel and see Sneaker Week. For better or worse, we’re hard-wired to pay attention to creatures that can eat us – even if they rarely do.

The Conversation

This article was originally published on The Conversation.
Read the original article.

Hunting for living fossils in Indonesian waters

The Coelacanth (Latimeria menadoensis) was thought to be extinct for more than 60 million years and took the science world by storm in 1938 when it was re-discovered living in South Africa. This fish has retained its features for 400 million years. Parts of its body, such as its back and belly fins, have an additional structure that resemble amphibian feet.

The fish, which has been spotted in the waters of East Africa, including South Africa, Madagascar, Comoros and Tanzania, also lives in Indonesian waters.

But to the Minahasan people of Indonesia, it used to be considered just an unusual member of grouper fish family. They call it “oil grouper”.

The Indonesian Institute of Sciences (LIPI) with the Japanese Aquamarine Fukushima are planning to build a centre for Coelacanth research in Bitung, North Sulawesi.

We chose this location because fishermen often accidentally catch the Coelacanth in the Sulawesi waters. Now that they know how extraordinary this fish is, they have started to tell us when they accidentally catch one. We hope that by working with fishermen, when they do catch a Coelacanth, together we will be able to do more to keep it alive and return it to its habitat.

As researchers, we are curious to learn more about Coelacanth’s reproductive system, feeding habits, growth, genetics and migration, because all that information can reveal more about the evolution of living species.

From a fish market to museums

A University of California scientist Mark Erdman and his wife first sighted the fish in Indonesia in 1997. They found it dead at the the Bersehati market in Manado. They took a picture and tagged it as specimen number CCC 174.

A year later, on July 30th 1998, Lameh Sonathan, a fisherman from the Manadua Tua island accidentally caught another Coelacanth. That second specimen is tagged CCC 175.

The Bogor Zoology Museum holds the specimen at LIPI’s Cibinong Science Centre. By the end of 2014, Indonesia had seven Coelacanth specimens located in various parts of the country.

Coelacanths have been sighted in the deep waters of eastern Indonesia.
from Marcio Jose Bastos Silva/

Where to find the Coelacanth in Indonesia

Recent research shows that the Coelacanth inhabits the waters in North Sulawesi and Papua.

In the last 15 years, research on Coelacanth in Indonesia has been focused on the area of North Sulawesi and its surroundings. In 1999, Max Planck Institute and LIPI worked together to record sightings of Coelacanth using a submersible called “Jago”, which translates as “cockerel” in Indonesian. The research recorded sightings of two Coelacanth in the Sulawesi Sea at 145 metres deep.

In 2006, LIPI’s research team and the Japanese Fukushima Aquamarine and Sam Ratulangi University recorded six Coelacanth sightings also in Sulawesi Sea 150 meters deep. A year later, the same team recorded nine Coelacanth sightings at Talise waters in North Sulawesi. In 2011, the research team sighted the fish in Biak waters in Papua.

Researchers believe it is probable that the fish lives in other areas of east Indonesia. The topography and the oceanographic conditions there are similar to Papua and North Sulawesi: rocky, steep and full of caves. Coelacanth live in deep waters of at least 150 metres, with temperature between 14 and 18 degrees Celsius. Their habitat are caves of rock structures in the bottom of the ocean.

There are still questions about the relationship between the Coelacanth in the East Africa coast and Indonesia. Researchers are trying to find answers through DNA testing.

By looking at its form, shape and structure, we can study how evolution happens, and how long the process of morphology changes occur. One of the ways to study the morphology is by examining x-ray photographs of the Coelacanth.

The study of the Coelacanth takes a long time, because of the very few specimens available. Intensive research is needed to find where significant numbers of Coelacanth live to ensure effective research and aid conservation.

The Conversation

This article was originally published on The Conversation.
Read the original article.

Shark-counting divers off Costa Rica reveal limits of marine reserves

Marine protected areas – essentially nature preserves in the ocean – are meant to provide a safe harbor for sharks, rays and other ocean species being lost because of intense and often unregulated fishing.

In a study published in Conservation Biology last week, we and other collaborators set out to quantify how populations of sharks and rays have changed over time at Cocos Island, a UNESCO World Heritage Site and one of the world’s oldest marine protected areas.

Perched 550 kilometers (340 miles) off the Pacific coast of Costa Rica, Cocos is an isolated paradise. Jacques Cousteau called it the most beautiful island in the world, and its lush rain forests were the inspiration for Michael Crichton’s novel Jurassic Park.

Underwater, Cocos teems with life. It is renowned amongst scuba divers as the best place in the world to swim with large schools of hammerhead sharks. Giant manta rays, sea turtles, yellowfin tunas, and whales sharks are also regularly seen.

And yet, there is trouble in paradise. We analyzed data on fish sightings reported after divemasters’ trips collected over the past two decades and found that all four of the most common shark and ray species at Cocos have declined significantly.

Ecosystem changes

Among the declines, we found the number of scalloped hammerhead sharks has dropped by almost half during that time. This tragedy is not altogether unexpected because hammerhead fins are highly prized in the international shark fin trade. These iconic sharks roam widely along coastlines in the eastern tropical Pacific Ocean, migrating between Cocos, Malpelo Island, and the Galapagos. Each of these islands is designated as a marine protected area, but hammerheads are still caught both within and outside of these areas.

More surprising, was the precipitous drop in Cocos’s other common shark and ray species, which inhabit the protected area year round. The whitetip reef shark is still seen on most dives at Cocos, but the number of this small reef-restricted species has plummeted by three-quarters. Ditto for the marble ray, a large stingray. Numbers of eagle rays, a large majestic pelagic species, have dropped by a third. All three of these species are thought to be reef-restricted and thus should be protected within the waters surrounding Cocos. Not so.

The declines in the number of sharks and rays restricted to the waters surrounding Cocos are a clear indication that the protected area isn’t working.

Genna Marie Robustelli, Author provided

We also found that there have been increases in a few species. Not a single tiger shark was seen by divers at Cocos in our data until 2000. These large distinctive sharks are now seen on over 10% of dives. The abrupt increase suggests that some tiger sharks have simply set up shop at Cocos. Observations of the blacktip shark and the Galapagos shark also increased in frequency, so the Cocos marine protected area may be working for these two smaller reef-restricted shark species.

One can point to the increases in tiger, blacktip, and Galapagos sharks as signs the protected area is working. This is probably partially correct. But it also reflects a larger shift in which species inhabit the waters around Cocos Island.

In other words, increases in several species may be a sign of larger problems caused by changes in the ecosystem around Cocos Island. Higher numbers of some species, in particular large predatory species such as the tiger shark, may alter the relationships between species already present.

Paper park?

On land, parks with inadequate enforcement against hunting are often referred to as “paper parks” – existing merely as boundaries drawn on paper but with little on the ground protection. This conveys a false sense of conservation.

Perhaps understandably, illegal fishing is rampant within the Cocos Island marine protected area: the island is remote, enforcement has been limited, and shark fins are a hot commodity. Cocos is a 36 hour boat ride away from the mainland. This remoteness is part of what makes Cocos such a draw for divers from around the world, but it also makes the island a sitting duck for illicit fishing activities.

Funding for monitoring and enforcement has been minimal. MarViva, a regional environmental NGO, has patrolled the island along with the Costa Rican Coast Guard since 2003 and caught illegal fishing in the process. Costa Rican laws make it tough to prove [illegal fishing] has occurred, however, and most cases to date have been dismissed in court. As a result, the illegal fishing continues.

A labour of love

Many divers, however, recognize Cocos for the treasure that it is.

Over the past 21 years, a group of dedicated divemasters working at Undersea Hunter, a live-aboard dive company specializing in trips to Cocos Island, has meticulously recorded every shark and ray they saw while diving at the island.

Our study synthesized their observations of over 1.4 million sharks and rays.

Genna Marie Robustelli, Author provided

Without these data, it would be impossible to know how underwater life at Cocos is changing. Like many parts of the developing world, Costa Rican waters are without dedicated marine research surveys or comprehensive fisheries data. The foresight of Undersea Hunter’s owner Avi Klapfer to begin their monitoring program, and the dedication of the divemasters to continue it over two decades, is a testament to their love of Cocos.

In this remote area, with no official monitoring, the Undersea Hunter data provide a window to see how sharks and rays have changed over two decades in this isolated and globally unique marine reserve.

Watching sharks and rays at Cocos, it is hard to believe that there used to be even more of these beautiful animals. The reef still appears to be covered with them despite the declines recorded by the divemasters over the years.

So what can be done?

More effort needs to be directed towards enforcement and monitoring at Cocos. Recent efforts by environmental non-governmental organizations (eNGOs), including MarViva, Forever Costa Rica, and Conservation International are encouraging. The groups are now working together, with assistance from Oceans 5, to install a radar on the island to help control illegal fishing. The Costa Rican government also needs to get serious about prosecuting offenders.

If Costa Rica is to maintain its status as a leader for progressive environmental policies, it needs to double down on efforts to protect its most iconic species and the national treasure that is Cocos Island.

To read more on the marine protection areas, see:

The Conversation

This article was originally published on The Conversation.
Read the original article.

Boom or bust in a jelly bloom market

The earth’s climate is changing and extreme weather events are on the rise. Hurricanes are wreaking havoc with more ferocity, summers are getting warmer and winters colder. But what about our oceans? They, too, are warming.

With the seas’ temperature rise has come an increased frequency of bloom events. These are rapid increases in the abundance of (normally) planktonic species, often associated with seasonal events or climatic phenomena. The duration of a bloom event depends on a number of environmental conditions, including temperature, light and nutrient availability. A well known example is the green algae that struck Qingdao, China during the 2008 Olympic sailing events.

10,000 people, including People’s Liberation Army soldiers, worked to clear algae before the 2008 Beijing Olympics.
Reuters / Nir Elias

With oceanic temperatures steadily creeping upwards, the general consensus is that such bloom events are on the rise in many areas. Although bloom events can cause significant problems in fisheries, some blooms can prove useful to fishers.

A recent study in the upper Gulf of California, also known as the Sea of Cortez, demonstrates just this relationship between fishers and blooms. Researchers from the Gulf of California Marine Program describe how in the summer of 2012, local fishermen were host to a huge bloom of non-native Cannonball Jellyfish (Stomolophus meleagris). Thanks to the fast-growing Chinese dried-jelly market, the bloom made the local fishermen US$3.5 million in just 40 days.

M Wukusick for GCMP, CC BY-NC-ND

Above-average surface temperatures and algal blooms promoted the growth of the jellies in the Guaymas basin, which is midway up the Gulf of California. These advantageous feeding conditions meant that what could have been a normal amount of jellyfish turned into a floating swarm. The jellies traveled north with the prevailing currents for 30 days until reaching the Santa Clara basin area of the Gulf, 750km north of Guaymas, where the bloom was fished.

The jelly bloom brought added revenue and employment to the upper gulf, but the story is not as rosy as it first seems. With such a large pulse to the local economy, and the assumption that the bloom would be a regular annual fixture, fishermen began investing in equipment and training courses (promoted by local fisheries managers) to prepare for the coming year’s anticipated harvest. Alas, in 2013, the jellyfish never appeared and the local fishers’ investment was lost.

Slimy catch during the jellyfish bloom in 2012.

With bloom events on the rise and many fish stocks facing unsustainable exploitation pressures, it seems clear that such jelly-fishery events will become more common in our seas and jellies more abundant in fish markets, albeit those in Asia. It is, however, important that careful investment is made in fickle fisheries stocks, like the jellies, that appear sporadically with low predictability. Similar stories of the rise and fall of cannonball jellyfish echo along the Southeast US continental shelf, but over longer and unpredictable time frames, highlighting the difficulty in relying on such blooms even over the longer term.

Cannon ball jellyfish washed up in the Gulf of California.
Iram Garcia GCMP, CC BY-NC-ND

If fishermen mis-invest and lose confidence in a fishery and local management, it will have negative consequences in the long term. The divide between rules – such as catch limits, closed seasons and protected areas – and compliance will likely widen as overall profits are reduced and the hunt for declining fishes increase.

In order to ensure full benefit is gained from new fishery opportunities without post-fishery “bust” scenarios, it is imperative that scientists, managers and fishers work together to make both economically and ecologically sound decisions based on long-term outlooks. Ways to get it right will include avoiding flooding markets and maintaining good market prices for catch, fishing within biological limits of species to prevent stock collapses and aid future stock booms, and using robust science, based on long-term data to make good predictions on future catches.

The Conversation

This article was originally published on The Conversation.
Read the original article.

Fur Seals Hunt Sharks off South African Coast

From movies like JAWS, to the real-life ordeal that was the sinking of the U.S.S. Indianapolis, sharks have had a fearsome reputation, as cold-blooded prehistoric killing machines of the ocean. It’s a reputation that led to severe overfishing of these monster fish in the mid-20th century. While they have been roving the ocean depths for over 300 million years, they’re hardly safe from predation.

In fact, humans aren’t even the only mammals that hunt down the great white shark for food. According to some newly discovered photos of a 2012 vacation to South Africa, large sharks have been preyed upon by fur seals. The photos were then used in a study published last week online in the African Journal of Marine Sciences. The discovery is important for several reasons – it reveals a staple of the seals’ diet that was previously unknown, but could be important for understanding the nature of the open ocean’s food web – the pattern in which ecological food chains interconnect.

Chris Fallows has worked with sharks since commercial cage diving began on South Africa’s coasts back in 1992. Now he manages the diving operation Apex Shark Expeditions, which makes him spend an average of up to 200 days per year at sea, where he gets to track and observe species of man-eating sharks. Despite all this background, he was particularly startled by the encounter he photographed back in December 2012.

Back then, Fallows led some tourists on what was a typical shark dive, about 20 nautical miles southwest from Cape Point, a fish hook shaped peninsula just on the outskirts of Cape Town. Nothing out of the ordinary: Fallows spotted ten blue sharks (the main culprits for the Indianapolis incident), who were drawn to the bait left out by his crew. Abruptly, however, Fallows received an unannounced visitor: a male Cape fur seal, one not yet fully matured. Rather than becoming the main course, this seal had other ideas, moving fearlessly into the hungry horde of blue sharks.

Cape fur seals typically eat small fish, squid or crabs, and they tend to be a favorite of great white sharks. In fact, nearly every shark attack oh humans is a case of mistaken identity, in which the sharks’ lateral vision causes them to mistake people for seals. It is also largely accepted that the people claimed by sharks in the Indianapolis wreckage had mostly died from other causes such as drowning, and the sharks simply cleared away their carcasses. Rather than grabbing fistfuls of bait, the hungry seal was interested in something else. It grabbed one of the feasting blue sharks, some of which were about four and a half feet in length, and as instinctively as it would try to break a clam shell, it ripped open the shark’s abdominal cavity and ravenously gorged on its liver.

Fallows feared for the tourists and ordered them back aboard the boat, but he was too intrigued to leave the scene. He photographed the small sea mammal as it tore apart five of the sharks in the pack. Then he left, fearing that his presence might be interfering with one of nature’s rare rituals. “Sharks of this size are certainly not usually considered food for seals,” Fallows said of the incident.

It actually wasn’t Fallows’ first time witnessing this scenario. Back in 2004, he sighted a similar occurrence at Cape Point, another young male fur seal male chasing and successfully capturing a blue shark, which it tossed into the air and then ate its stomach and liver, which make up the most energy dense and protein rich portions of the fish. Unfortunately, he wasn’t able to capture the event in pictures, but the ones in 2012 he decided to post online, attracting a great deal of attention from both amateur fishermen and the scientific community at large.

Among those intrigued was Hugues Benoit, a fisheries scientist at Fisheries and Oceans Canada. “I saw these images—beautiful images—and contacted Chris,” said Benoit. “I wasn’t sure if he understood the scientific importance of what he had seen.”

In their new paper on the occurrence, Fallows, Benoit and Neil Hammerschlag of the University of Miami have described the event in somewhat graphic detail as well as the ecological significance. Although it isn’t uncommon for seals to sometimes snatch baby sharks or to gnaw on dead sharks found in fishing nets, this phenomenon might be representative of predatory competition seen in a marine setting – similar to how primitive humans competed with the cave bear and dire wolf for food. The Cape fur seals and blue sharks both tend to have similar diets, but seals had never been seen attacking their competitors. “This is a case where one competitor sort of got the upper hand,” said Benoit.

The team has also noted the seal’s peculiar habit of only eating the visceral organs. Seals had already been seen eating these organs on large fish caught in nets, but the practice is rarely observed among marine mammals going after the prey as it swims. Because the seal isolates and tears away to a specific, nutritious part of its prey suggests that it may have a wealth of food resources.

“It’s like being at a lobster buffet,” Benoit says. “If there’s tons of lobsters around, you just eat the tails and claws instead of dealing with all the little legs.”

The fact that this behavior was only documented recently may indicate that the traditional means by which researchers calculated the diets of marine mammals might be leaving some gaps in the food web. Ecologists once assumed that seals primarily subsided on small fish less than a foot long. Typically, they determine what seals consume by looking through the remnants in their guts or fecal matter, but this usually is dependent on recovering hard remnants, such as bone, while sharks largely contain cartilage except for their teeth. These organs could be rapidly digested with little evidence.

Lastly, the realization that the seals are only after viscera can also have long-reaching implications for shark populations, as it means the seals will target multiple animals before eating its fill. However, they have yet to give accurate estimates on how many blue sharks may be sharing this fate. Benoit, however, thinks that the pattern of shark-eating behavior may be normal, taking place in open water where human presence is an unusual occurrence. Fallows recalled being “impressed at the ease with which this seal was able to take these sharks,” testimony that may suggest it was hardly the first time that his seal attacked a pack of much larger sharks. Blue sharks are in decline in the Pacific Ocean due to overfishing for shark fin soup, despite the soup being banned in most countries.

“Presumably, this kind of behavior would be rare enough that the observer would just have to be at the right place at the right time,” Benoit said. “Although this is just a few observations, it shows that, in some instances, human observers can overcome the somewhat improbably odds of capturing these kind of events on film.”

James Sullivan
James Sullivan is the assistant editor of Brain World Magazine and a contributor to Truth Is Cool and OMNI Reboot. He can usually be found on TVTropes or RationalWiki when not exploiting life and science stories for another blog article.