Survival against all odds: Animals of the Arctic
Adaptation is fundamental for a species to survive, especially in hostile environments like the Arctic. When faced with six months of perpetual darkness where snow and ice lays claim to every inch of the land. What kind of extraordinary animals survive in such harsh terrain, and more importantly, how do they do it? During winter in the Arctic, temperatures can drop to a bone-chilling −50°C (−58 °F). Rather than going into hibernation however, some animals will stick out the winter and use their cold-conquering adaptations to survive. This BBC Earth blog takes a look at the Arctic Fox, and the Walrus - a master at retaining body heat.
Walrus are covered with short coarse hair that becomes less dense as they get older. Their skin which is folded and wrinkled can be up to 4 cm thick serving as a great insulator. This tough skin is the thickest on the neck and shoulders of adult males where it also serves as a defensive purpose – when these bulls spar the thick skin is intended to resist tusk penetration. They have a deposit of fatty tissue that is up to an astounding 15 centimetres (6 inches) thick - in winter it may make up to a third of their body mass. As well as being an excellent insulator it also streamlines the body and is used as an energy reserve. Their outer defences serve as a pretty hardy armoury but even this thickest of ‘winter coats’ is not sufficient when diving to depths of over 180 meters for nearly half an hour at a time, so the walrus has another trick up its sleeve. When they enter the cold arctic water they become paler because they have a mechanism that restricts blood flow to the skin in order to reduce heat loss. Conversely, when walruses are warm their skin is flushed with blood and they appear to be very red. The adaptations that allow animals to live in such a hostile environment are incredible; join us again when we check out some even more incredible adaptations – those of the animals who inhabit the coldest place on earth, the Antarctic.
BBC... How we tell intimate stories
Our world may be very big, but sometimes it is the smallest stories that teach us the most. BBC Earth brings you three incredible videos where an innovative use of technology has captured the true magic of nature. Click the link above the view all three videos.
Developing technology to capture the minuscule and the marvelous is one thing, but what happens when what you’re trying to film is located underneath eight feet of solid ice? Producer Neil Lucas gives us an insight into the incredibly rewarding, but painstaking task of filming in these challenging conditions.
Armed with a passion for the natural world and the desire to communicate its incredible stories, BBC Earth filmmakers will continue to surprise and delight us for years to come.
Experts save dolphin from fishing line entanglement
Animal experts this week have successfully removed tangled fishing line from a dolphin calf off the coast of St. Petersburg, according to NOAA. The calf and its mother were first spotted in late July, but were not seen again until late October. The calf was entangled in fishing line that was cutting deeply into its mouth and dorsal fin. The calf was successfully located this week during the first rescue attempt, within a quarter mile of the Veteran's Park boat ramp just after sunrise. The calf was restrained and it was discovered that the line was running through the calf's mouth, cutting into its jaw, wrapping around its right flipper and cutting several inches into the dorsal fin. Once the line was removed, the calf was given an antibiotic and released.
Fury as minister delays marine protection
The government has been accused of failing the environment after announcing delays to the creation of marine reserves. Conservation groups responded angrily to the announcement by environment minister Richard Benyon that the internationally agreed deadline for creating marine protected areas will be missed. They accused the government of changing the rules at the last minute on how valuable marine habitats should be identified to protect them from destruction by vested interests. In his statement Mr Benyon said that the government wanted more evidence gathered before it made a decision on which locations, and the wildlife in them, should get priority for protection. But conservation groups quickly pointed out that the government had, from the outset of the process of identifying where a network of marine reserves should be created, accepted there was a shortage of detailed scientific evidence of what lies beneath the waves and that suggestions should be assessed on the basis of “the best available evidence”. The fear is that when there is a lack of evidence about a location, vested interests such as fishing, aggregates, oil & gas, and renewable energy schemes, will be allowed to exploit the area when in reality they harbour rare or valuable animal communities. The demand for more evidence means the first marine conservation zones, as part of the Marine and Coastal Access Act, will not be in place until at least 2013. It also means that just a fraction of those initially promised form the first tranche.
WWF: Ban bluefin farming
WWF has released a new study showing current fishing capacity doubling bluefin tuna quotas in the East Atlantic and Mediterranean and points to the need to strengthen the current capacity reduction plan. In addition, WWF urges the International Commission for the Conservation of Atlantic Tunas (ICCAT) this year to ban bluefin tuna farming. WWF says it will focus on assessing implementation of the current bluefin tuna recovery plan. In addition the Mediterranean swordfish will be high on the agenda. WWF urges ICCAT to adopt a management plan for this species, the first one ever. Although efforts have been made in the last few years, new reports suggest that IUU fishing remains widespread in the Mediterranean, particularly in Libyan waters but also in Italy. The new WWF study on the fishing capacity of the Mediterranean bluefin tuna fishery points out that huge overcapacity is still prevalent. In the period 2008-2010 estimates of potential annual catches amount to between 31,500-34,000 tonnes, considerably higher than the current TAC, leaving ample room for IUU fishing. According to WWF, sustainable management of the bluefin tuna fishery still needs to be achieved and IUU must be fully eradicated. In particular WWF urges ICCAT to ban fishing in Libyan waters and to turn this area into a BFT Sanctuary. Regarding tuna farming, WWF says a recent scientific study submitted to ICCAT Scientific Committee (SCRS) this year shows that biomass growth in farms is typically much lower than that reported by the farming industry (only 20-30%, compared to given values of over 100%), which raises concern over the potential for laundering bluefin tuna catches in Mediterranean farms. Full traceability in farms continues to be impossible as there is no way to know how much tuna is transferred to the farms. WWF urges ICCAT to ban bluefin tuna farming and to adopt an electronic catch documentation system (BCD) to allow for real time traceability. On swordfish, WWF calls on ICCAT to adopt a science-based recovery plan this year including a mandatory capacity reduction multi-annual plan.
Endangered Sea Turtles Threatened by Delay in Federal Help
San Francisco's federal government missed a court-ordered deadline today to protect habitat for endangered leatherback sea turtles off the U.S. West Coast. Instead of publishing its final rule to protect the turtles, the National Marine Fisheries Service sought a delay from federal court, leaving the increasingly rare leatherbacks vulnerable to threats from fishing, new coastal development, offshore energy and aquaculture. Oceana, TIRN and the Center for Biological Diversity have asked the court to deny this latest attempt by the Fisheries Service to delay protections for the ancient turtles. The request comes after years of repeatedly missed deadlines, lawsuits and a settlement agreement that already gave the Fisheries Service nearly an additional year (until November 15th 2011) to finalize overdue critical habitat protections for the imperiled animals. In order to survive, leatherbacks need safe passage from nesting beaches 6,000 miles away in remote Indonesia to feeding hotspots in Pacific Ocean waters off California, Oregon and Washington. Protection of the key migratory corridors and feeding areas in these waters were elements of the critical habitat designation. Once established, habitat protection could limit activities that harm the leatherbacks’ main prey, jellyfish, or impede their migratory path. The largest of all sea turtles, leatherbacks can grow to be up to nine feet long and weigh up to 1,200 pounds. Pacific leatherback sea turtles have declined more than 95% since the 1980s; as few as 2,300 adult female western Pacific leatherbacks remain. The species has survived for 100 million years virtually unchanged; now it risks disappearing.
Migrating whale numbers hit 50-year high
There has been a rise in the number of migrating whales. They travel on a 5,000km (3,100 miles) round trip to give birth off the coast of Australia before heading back to Antarctica to their main feeding grounds. It is the highest number seen in half a century. Duncan Kennedy reports from Sydney is this BBC video.
Less than 1% of sharks caught in the Atlantic are protected
Only a tiny fraction of sharks caught in the Atlantic – less than 1% – are under protection, even though most shark species are heading towards extinction. Officials from 48 Atlantic fishing countries are meeting in Istanbul this week to try to protect bluefin tuna, swordfish and other large fish. But existing conservation efforts are only saving a tiny proportion of sharks, the report from the Oceana conservation group said. Conservation groups at the International Commission for the Conservation of Atlantic Tuna (Iccat) meeting are pushing for a ban on the catch of porbeagle and silky sharks – which are at extreme risk – as well as catch limits on other species such as the shortfin mako shark. Three quarters of the wide ranging shark now being caught in the Atlantic are under threat, the report said. But Iccat countries to date have only limited protection for specific shark species such as the bigeye thresher, hammerhead and oceanic whitetip sharks. There are no limits on the fishing of 15 Atlantic shark species even though some – such as the silky shark – are close to extinction. Conservationist groups hope the Istanbul meeting will build on recent momentum on shark conservation. But it is a race against time. Sharks were not built for reproduction. They can take take years to reach sexual maturity, and produce only a few pups. And highly mobile animals are notoriously difficult to protect. Atlantic fishing countries reported catching more than 68,000 tonnes of shark in 2009, or more than 1.3 million animals. Most were caught inadvertently by vessels targeting tuna and other fish. Populations of some species, such as the porbeagle, which are caught for their meat as well as their fins, have fallen by 99% since the middle of the last century. Scientists estimate it could take up to 34 years for populations to recover – even with the new EU protections. Fishing of porbeagle sharks continue in Canadian waters. Three other shark species are also at high risk: silky sharks, shortfin mako, and blue sharks, the report said.
New underwater model to assess noise impact on marine life
HR Wallingford, the international hydraulic and environmental engineering consultancy, has formed a partnership with Loughborough University to develop a new underwater acoustic propagation and noise-impact model. Designed to work with proven HR Wallingford ecological models, the new model is an important first step in assessing the impact of underwater noise on fish and sea mammal behaviour. It can be applied in marine renewable energy, oil and gas extraction, dredging and other settings. The significant noise generated by marine construction and operation, and its possible effects on marine life, have come under increased scrutiny worldwide. Where activities take place in and near sensitive marine areas, there is particular concern. Within the European Union, sound is now a recognised pollutant at both project and regional seas levels. In the UK, construction has started of ‘Round 3’ windfarms, some of the largest to be built in British waters, and there is an urgent need to understand their impact on marine life. The model uses temporally and spatially varying parameters such as tidal water depth, flow velocity, salinity, temperature and bathymetry from HR Wallingford’s hydrodynamic model simulations. Modelled noise amplitude and frequency are used as inputs, or ‘behavioural cues’. These are then inputted into HR Wallingford’s established and successful dynamic ecological response models, enabling users to assess marine-species responses to human disturbances.
Untangling Grassholm's gannets
Close to forty thousand gannets spend the breeding season on Grassholm each year, making it a raucus, bustling seabird haven. Most of the birds leave in Autumn, but a few stragglers remain. Sadly, some of these remain because they are tethered to the ground by plastic line, strapping bands, nets, and other materials which the birds use for their nests. MCS Communications Manager, Richard Harrington, and Litter Policy Officer, Dr Sue Kinsey, spent the day with Grassholm's RSPB wardens. They saw the entrapment first hand, and helped free some of the ensnared birds. Most trapped birds we found were ensnared by one or both legs. The material would have wound itself many times around as the bird struggled to free itself, giving no chance of escape. It was satisfying to cut this from an otherwise healthy bird, and especially so when one or two of these immediately flew out to sea. Of the other survivors, wings would be snagged and sometimes broken, or bills and necks wrapped in a tight loop of line; these could be freed, but not always saved. Some carcasses on the ground showed signs of having swallowed quantities of line and fabric. In total, twenty seven birds were freed, each with a better chance of survival than before. This was an improvement on the previous year, when more than a hundred chicks had needed assistance. The sheer volume of plastic material on view is striking, but warden Greg Morgan explained that it just isn’t practical to remove it, and would ruin the fabric of the nest sites to do so. He has taken sample sections from a nest, finding decades-worth of accumulation put together by generations of gannets. Anything resembling a colourful bit of seaweed has been used. Balloon ribbons and attachments are commonplace, and lengths of pipe (a little like kelp stipes) stand proud of the floor. They will be there for many generations to come. The birds freed represent only a tiny fraction of the site’s breeding population and so, despite the obvious suffering, it can’t be considered a threat to the species’ continued existence here. It does, however, serve as a graphic reminder of just why MCS needs to keep up the anti-litter message, and to seek to find ways to reduce the sheer volume of waste entering the sea.
Crane lift for eel as 'love congers all' in Macduff
A 6ft conger eel has been released into the wild so he can find love after a lifting operation involving a crane. The conger eel, called Rip, left Macduff Marine Aquarium in Aberdeenshire to swim to the Atlantic. Staff said he had become restless, a typical sign that the time had come for a 2,000-mile migration. The eels are known to congregate in deep water, where they spawn before dying. Operation Rip Tide was carried out on Monday afternoon. Rip has been at the aquarium since 2004. A large bag was used to catch the conger eel and a crane was used to hoist him out, lowering him into sea, where divers opened the bag. Claire Matthews, the aquarium manager, said: "We hope Rip makes it to the Azores, but of course the sad part of the story is that he will die after it all - but at least he'll be happy." In 2001, Chippie the conger eel was released at the aquarium for the same journey in Operation Amour.
Volcano Near El Hierro, Canary Islands Releases Toxic Gases
An underwater volcano near El Hierro in the Canary Islands has begun erupting near the shore, reports Reuters. The eruptions may be spectacular, but officials have also noticed that the volcano is spewing toxic gases into the air around the island. After a worker studying the volcano became ill, several of the island's beaches were closed. In the video, a local explains that the volcano is also making the island's cats act strangely and eat dead fish. The volcano, which is just over 200 feet from the surface, began erupting a week ago and is shooting magma 65 feet into the air. The eruption is the first in the Canaries since 1971 and locals are already speculating that it may create a new island. Despite the beach closures and dead fish near the island, the island's human population is safe.
22 sperm whales die in Australia
Rescuers are racing against the clock to save two huge sperm whales stranded on a Tasmanian sandbank after 22 others died, the Parks and Wildlife Service says. Marine mammal specialists were on site in Macquarie Harbour at Strahan on Tasmania's northwest coast, but it was proving to be a slow process. Twenty-two of the whales weighing two tonnes and up to 12-metres- (40-feet-) long washed ashore on Saturday at Ocean Beach near Strahan and all of them died. Four others came into the harbour and stranded themselves on a sandbank. Two were successfully refloated and swam back out to sea but two remained stuck. Tasmanian Parks and Wildlife incident controller Chris Arthur said sperm whales were so big they could not simply be pulled into deeper water by volunteers. Conditions were worsening with high winds and seas hampering efforts, but Arthur expressed confidence after seven sperm whales were saved in a similar stranding in the harbour in 2007. Whale beachings are relatively common in Australia, and they usually occur in the summer months around December around Tasmania.
Sea Levels to Continue to Rise for 500 Years? Long-Term Climate Calculations Suggest So
Rising sea levels in the coming centuries is perhaps one of the most catastrophic consequences of rising temperatures. Massive economic costs, social consequences and forced migrations could result from global warming. But how frightening of times are we facing? Researchers from the Niels Bohr Institute are part of a team that has calculated the long-term outlook for rising sea levels in relation to the emission of greenhouse gases and pollution of the atmosphere using climate models. The results have been published in the scientific journal Global and Planetary Change. "Based on the current situation we have projected changes in sea level 500 years into the future. We are not looking at what is happening with the climate, but are focusing exclusively on sea levels," explains Aslak Grinsted, a researcher at the Centre for Ice and Climate, the Niels Bohr Institute at the University of Copenhagen. He has developed a model in collaboration with researchers from England and China that is based on what happens with the emission of greenhouse gases and aerosols and the pollution of the atmosphere. Their model has been adjusted backwards to the actual measurements and was then used to predict the outlook for rising sea levels. The research group has made calculations for four scenarios: a pessimistic one, an optimistic one, and two more realistic ones. In the pessimistic scenario, emissions continue to increase. This will mean that sea levels will rise 1.1 meters by the year 2100 and will have risen 5.5 meters by the year 2500. Even in the most optimistic scenario, which requires extremely dramatic climate change goals, major technological advances and strong international cooperation to stop emitting greenhouse gases and polluting the atmosphere, the sea would continue to rise. By the year 2100 it will have risen by 60 cm and by the year 2500 the rise in sea level will be 1.8 meters. For the two more realistic scenarios, calculated based on the emissions and pollution stabilizing, the results show that there will be a sea level rise of about 75 cm by the year 2100 and that by the year 2500 the sea will have risen by 2 meters.
Whale is freed from fishing nets off Dunbar
A 40ft-long whale has been successfully freed from fishing
gear off the coast of East Lothian. The humpback was reported trapped in a boat's nets on Tuesday. It escaped but
was then trapped again in a line of creels off the Dunbar coast. The whale had suffered serious injuries to its back and dorsal fin but
experts believe it will make a full recovery. A team from the British Divers Marine Life Rescue was helped by Dunbar
Lifeboat.
That's all for this edition of the Marine News Roundup - there will be another in two week's time.
Another thought provoking blog and I look forward to the next one.
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