Friday, 28 August 2015

The evolution of whales

Whales, dolphins and porpoises, collectively known as cetaceans (for their classification in the mammalian order Cetacea) have long captured the attention of humans. From early drawings etched on the walls of Paleolithic caves, to 21st century satellite tags tracking the underwater movements of these denizens of the deep, the lives of humans and whales have been inexorably entangled. This connection has been a compelling story of the discovery and scientific study of large, charismatic sea animals tempered by darker times of intense human hunting and whaling that left many species hovering on the brink of extinction.

The approximately 90 living species of cetaceans inhabit nearly every ocean basin in addition to a few river systems, occupying diverse habitats that include polar, temperate and tropical waters. Whales evolved more than 50 million years ago in present-day India and Pakistan. Evidence from anatomy as well as genetics supports a close relationship between whales and even-toed ungulates (e.g. deer, giraffes, hippos, pigs, cows) with hippos positioned as their closest kin. The land to sea transition made by whales involved anatomical and physiological adaptations (e.g. feeding, locomotion and respiration) that are well represented in the fossil record. For example, recent discoveries indicate that the earliest whales like their terrestrial ancestors had well developed fore and hind legs and lived on land as well as the water.

One of the best-documented examples of evolutionary change in the fossil record is the loss of hind limbs in whales and recent study of whale embryos has revealed its genetic basis.

Whales are divided into two major groups: odontocetes (toothed whales) and mysticetes (baleen whales). Odontocetes are more diverse with 76 living species compared to 14 species of mysticetes. As the name suggests odontocetes possess teeth and most eat fish although some have very reduced dentitions and are specialized for suction feeding squid.

A key adaptation that enables odontocetes to pursue prey involves using high frequency sounds produced in the nasal region.

Mysticetes do not echolocate and recent research suggests that they may find prey using sensitive vibrissae (whiskers) on the rostrum. Although mysticetes possess teeth at birth (also present in early fossil mysticetes) they are resorbed and adults feed using baleen, keratin based structures. Plates of baleen are suspended in racks from their enormous mouths that act as a comb to bulk filter feed large aggregations of fish and zooplankton.

The biology of whales has been enriched by remarkable recent advances in integrated research in paleontology, ecology, behavior, and genetics. Modern techniques such as attaching digital acoustic tags (DTAG) to whales have elucidated extraordinary feeding behaviors and foraging strategies. Not only do these tags provide information on body orientation (i.e. acceleration, pitch, roll and heading) they also record sounds made by and heard by the tagged whale as well as recording environmental parameters such as water temperature and depth. Isotope studies reveal ocean temperature changes through time providing evidence that the diversification of modern whales was associated with increased food production.

Exciting breakthroughs in understanding the anatomical structures and pathways involved in sound production and reception in whales have been facilitated by CT scans and 3D imagery. Genetic and genome studies have explored evolutionary relationships among cetaceans as well as providing valuable life history and population data critical to the development of thorough management and conservation plans.

Knowledge of the biology of whales provides a framework that is essential for helping us understand how best to protect and conserve them. Further, as top predators, whales are indicator species of the health of the ecosystem and serve a vital role as sentinels of climate change.

Beautifully illustrated throughout, “Whales Dolphins and Porpoises” edited by Annalisa Berta, combines highlights from the latest scholarly studies of the nature and behaviour of the world’s whales, dolphins and porpoises, with a fully comprehensive species directory, that offers detailed profiles of each species alongside all the information needed to identify them in the wild.

Annalisa Berta has been Professor of Biology at San Diego State University, California, for more than 30 years, specialising in the anatomy and evolutionary biology of marine mammals. Past President of the Society of Vertebrate Palaeontology and co-Senior Editor of the Journal of Vertebrate Palaeontology, Berta has authored and co-authored numerous scientific articles and several books for the specialist and non-scientist.

Edited by Annalisa Berta
Available 21 September 2015
ISBN: 978-1-78240-152-0

Wednesday, 10 June 2015

Are we winning the battle to save sea turtles?

We have come a long way since early conservationists started with many beleaguered nesting sea turtle populations in the middle to the late part of the 20th Century. Nesting turtles are now protected in many countries around the world, there are now very few large legal harvests, and many populations, such as the one we study in Ascension Island have begun to recover incredibly well.

Leatherback sea turtle released from fishing net. Pic: Tim Collins, WCS

I feel that the level of awareness of sea turtle conservation and goodwill towards this charismatic animal group is at an all-time high. This is down to a tremendous cadre of people (many thousands) who work tirelessly for turtles across the globe. Sea turtles are a good news story and cause for ocean optimism. There is, of course, still work to be done.

The challenge now, is to look after turtles in the sea as the main threat to sea turtles is in incidental capture in fisheries (bycatch). There has been much focus on large-scale driftnets, longlines and trawlers and a great deal of progress made. Recently it has become ever more apparent that because of where they operate and their very large numbers that coastal and inshore fisheries are responsible for very high levels of bycatch. It may be that each vessel does not catch many, but when scaled up their impact can be substantial e.g. in Peru.

Illegal trawlers in Conkouati-Douli National Park.  Pic: Tim Collins, WCS

To effect change, however, fishers need to be engaged in the process. As a case in point, I outline a current Darwin Initiative Project we are supporting in Conkouati-Douli National Park in the Republic of Congo, Central Africa. The park plays host to important populations of elephants, chimpanzees and lowland gorillas but also has important aggregations of nesting olive ridley and leatherback sea turtles and humpback dolphins. These are co-located with impoverished people living in coastal areas who have high degree of fisheries dependence and limited alternative livelihood opportunities. There is a modest degree of turtle bycatch, but perhaps of greater concern is the much larger effort associated with unregulated trawl fisheries who are a source of conflict with the artisanal fishers and has an, as yet, unassessed impact on marine turtles.

Fishermen in Conkouati-Douli National Park. Pic: Tim Collins, WCS

Using a participatory approach, artisanal fishers are volunteering to carry GPS trackers to map their activities in high resolution, allowing us to assess their footprint, possible bycatch interaction hotspots and integrate their needs into future marine spatial planning for marine protected areas that can have maximum benefit to biodiversity (and ultimately fisheries as a result of spillover) with minimal cost to stakeholders. These data will hopefully feed into the development of a marine plan similar to that in neighbouring Gabon, which is also of global importance for marine turtles, which has recently announced a new network of marine parks that will comprise 23% of its EEZ.

Olive ridley sea turtle in Conkouati-Douli National Park. Pic: Brendan Godley

Although the well demonstrated threats of direct take, habitat loss and degradation may still be of concern to some populations, and we must consider emerging threats such as climate change and marine plastic pollution, artisanal and small scale fisheries is the key area on which I believe we must focus our efforts. A more coherent ecosystem based approach is undoubtedly important. Moreover, progress in this regard is crucial to sustain the livelihoods of many millions of coastal people who are so dependent on the sea for nutrition and employment. 

Brendan Godley is the Professor of Conservation Science/Director of the Centre for Ecology & Conservation at the University of Exeter. Follow Brendan on Twitter @BrendanGodley

Wednesday, 20 May 2015

Deep-sea sharks in danger

The dark, cold, crushing depths of one of the world’s largest ecosystems is home to about half of all known shark species. However, living at depths between 200-3000m, these deep-sea species aren’t your typical sharks. Armed with sharp defensive fin spines, large reflective eyes, and, in some cases, an ability to glow in the dark, these alien sharks could be the stars of a science fiction horror movie. But with a biology specifically adapted to deep-sea living, the sharks themselves may be the ones who experience the horror, as fisheries move ever deeper into their deep-sea world.

Portuguese dogfish  (Centroscymnus coelolepis) Pic: Alan Jamieson

If you watched the latest BBC “SHARK” trilogy, you will have seen cameos from the Greenland shark, Frilled shark and Goblin shark. Using new technologies the BBC was able to capture some truly revolutionary footage of these enigmatic creatures. But just as they have begun to whet our interest, they are becoming increasingly threatened by an expanding fishing industry. The very features that make these sharks successful deep-sea predators have ironically made them vulnerable to man and his ships.

Longnose velvet dogfish (Centroselachus crepidater)

Life in the deep-sea is challenging due to the lack of baseline nutrient production. Instead, the deep-sea must rely on the transport of nutrients from surface waters to fuel their food webs. Put simply, food down here is quite scarce. To survive down here, sharks have had to adapt.

Like most other deep-sea fish, the deep-sea sharks have a very low metabolism. One theory behind this is that due to the lack of light, there is no need to be a fast active predator [1]. Chasing down prey is too risky and energy demanding. When feeding events are rare and often opportunistic, it makes sense to have a biology that inherently conserves energy. Furthermore, these sharks are slow-growing and long-lived. Some scientists estimate that the Greenland shark can live in excess of 100 years [2].

Velvet belly lanternshark (Etmopterus spinax)

The way these sharks reproduce also has a substantial effect on their vulnerability. Deep-sea sharks tend to reach maturity at a much later age than shallower water sharks, have fewer offspring and have long reproductive cycles. The Leafscale gulper shark could almost star alongside Steve Carrell in the 40-year old virgin movie, as it is believed it doesn’t reach sexual maturity until 35 [1]! Investing more energy into producing fewer, large, developed offspring, females maximize the chances of their pups surviving in this challenging deep-sea world.

To handle the crushing pressures of the deep, these sharks have very large oily livers, which they use for buoyancy. In order to maintain such oily livers, it is important to feed regularly [3]. Deep-sea sharks literally face the risk of starving or sinking to their death if they don’t feed often enough. Therefore, deep-sea sharks don’t stray too far into the deep, where food is even scarcer and subsequently are rarely found below 3000m.

Leafscale gulper shark (Centrophorus squamosus) Pic: Joao Correia

Unlike pelagic and coastal sharks that are targeted mainly for their fins, deep-sea sharks are targeted for their large livers. Squalene, a main component of shark liver oil, is used in a wide range of items including face creams, dietary supplements, vaccines and a variety of medical products, and it can fetch a high price in many markets.

It’s almost the perfect storm in terms of an animal’s vulnerability to fisheries. Having large livers, slow metabolism and specific behavioural traits, these sharks have become top deep-sea predators. But with fisheries targeting them for these livers, and a biology that means population recovery is slow, these deep-sea sharks are clearly under serious threat. Whilst Europe has recognized this and prohibited the landing of any deep-sea shark, the rest of the world has yet to follow suit.

We are still trying to unravel the mysteries of many of these alien ecosystems and assess the impact that continued exploitation will have. We are in grave danger of not only never seeing these fascinating sharks in future wildlife documentaries again, but also losing them from our oceans completely before we have fully understood their importance to the planets health. 

1: Rigby, C. & Simpfendorfer, C. Deep-Sea Res II, 115, 30-40 (2015)

2. MacNeil et al. J. Fish. Biol. 80, 991-1018 (2012)
3 Musick, J. A. & Cotton, C. F. Deep-Sea Res. II. 115, 73-80 (2015)

Christopher Bird is a Ph.D student at the University of Southampton and The National Oceanography Centre. Having worked with many shallow water sharks during his early education, he is now dedicating his research to understanding the trophic and spatial ecology of deep-water chondrichthyans in the Northeast Atlantic. Follow Chris on Twitter @SharkDevocean & blog

Monday, 13 April 2015

In the company of dolphins

The Moray Firth and North East coast of Scotland are home to a resident population of bottlenose dolphins, around 200 or so in number and I am fortunate to spend my working life studying and photographing these big, charismatic predators.

Bottlenose dolphins in the Moray Firth

A boat is not always necessary to get access to these dolphins, as they can hunt for seasonal migratory salmon only a few metres from the shore of one particular peninsula – Chanonry Point on the Black Isle near Inverness. I am able to monitor which individual dolphins are using the area by recognising them through their very individual dorsal fins – a technique called “mark recapture”. I often share these pictures and data with my friends at Aberdeen University’s Lighthouse Field Station at Cromarty who run the official Photo ID project.

"Mark recapture" of bottlenose dolphin dorsal fin

These dolphins are also highly individual in nature, not just in dorsal fin appearance and have very distinct personalities that you get to know when you study them for an extended period – we are talking decades here as these are long-lived mammals – 50 years or so for females isn't uncommon. I have the honour of having a young male dolphin named after me ID#1025 “Charlie” who is the son of “Kesslet” whom I have studied for 20 years. The work that I do for the charity Whale and Dolphin Conservation (formerly WDCS) is to study 6 individuals in particular that the public can “adopt” and support us financially, constantly supplying my support team at head office with the raw ingredients to keep the programme going. It might sound all very romantic, studying dolphins for a living - but up here in northern Scotland it can be hard, arduous work, especially in the winter when the weather is challenging and the dolphins are farther out to sea hunting winter prey like herring.

Bottlenose dolphin and salmon

To photograph these dolphins from the shore I use some of my professional photography “toys” to get as good images as I can. You will see me throughout the year standing at Chanonry Point with my huge white Canon 500mm lens and high frame rate IDX camera body mounted on a big carbon fibre tripod getting pictures of the dolphins and observing their behaviour as they move in and out of the area. If I am lucky enough to get out with Aberdeen University or maybe one of the local tour boats in good weather then I can top up my image bank of dolphins out at sea using much smaller zoom lenses. When out on the Moray Firth I can come across individuals that I might not encounter around Chanonry very often as some of these dolphins have their own favourite areas and might not visit my “office” that frequently. It's great fun catching up with other dolphins that I haven’t seen for a while, especially the females if they have had new babies. Although I have been doing this for a long time now, I still feel my heart-rate increasing whenever I see a dorsal fin and I never get tired seeing them – I just love being in the company of my dolphins.

Charlie Phillips at his "office" on Chanonry Point

Charlie Phillips is an award-winning professional wildlife photographer, lecturer, and author who was Scottish Nature Photographer of the Year 2012. He is also Field Officer for marine mammal charity WDC. Follow Charlie @adoptadolphin on Twitter. His new book “On a Rising Tide” will be available in Autumn of 2015. 

Friday, 27 March 2015

The importance of plankton

Without plankton there wouldn’t be polar bears on the ice.

Phytoplankton and copepods are the first two steps in the plankton food chain

In the sea, the plankton begin the marine food chain. Microscopic phytoplankton (tiny plant-like cells) use the sun's energy to combine carbon dioxide and water to create sugar and oxygen in the process known as photosynthesis. Despite being tiny (each phytoplankton cell is smaller in diameter than a strand of human hair), they are so numerous that they account for about 50% of all photosynthesis on Earth. And here, tiny creatures and big numbers start to mix, since 50% of all photosynthesis equates to about 50 billion tonnes of carbon each year, or about 125 billion tonnes of sugar!

The phytoplankton are the food of herbivorous zooplankton (animal plankton) in turn eaten by carnivorous zooplankton. Together all the plankton are the food for fish, which in turn are eaten by other sea creatures such as seabirds, sharks, and seals, in their turn eaten by larger predators like killer-whales. The plankton are also the food source of some of the largest mammals on Earth, the baleen whales. In this way the plankton food web underpins and determines the amount of life in the sea. Quite simply, without the plankton there would not be any fish in the sea for you, me or other creatures to eat, and so that is why there wouldn't be any polar bears on the ice.

The author and plankton scientist Dr Richard Kirby

Of course, as well as eating fish, we also consume many marine creatures that had a larval life in the plankton such as shrimps, crabs, and mussels etc. In some countries we also eat plankton too, such as Antarctic krill that is eaten in Japan as Okami. In fact, in Britain during the Second World War there were trials in Scottish sea lochs to determine whether large static nets could harvest sufficient plankton to supplement the national diet should food become scarce. While those early Scottish trials in the 1940s proved unsuccessful, today, a commercial copepod harvest for food for aquaculture occurs in some Norwegian Fjords by using large nets towed by trawlers.

Now, we need to pay attention to the plankton more than ever. Living at the sea surface the plankton are particularly sensitive to changes in sea surface temperature, which is influenced by the air temperature above. (We often forget that we can engineer our thermal environment unlike other life on Earth that lives where the temperature suits it best.) My research and that of other plankton scientists, is revealing that rising sea temperatures due to current climate change are altering the abundance, distribution, and seasonality of the plankton throughout the oceans with ensuing ramifications for the marine food chain, our commercial fisheries, and the wider marine ecosystem.

Unfortunately, in this short blog there wasn't time to tell you how the plankton do so much more than just support the marine food web. However, you can find out how much more by watching my short film Ocean Drifters, a secret world beneath the waves, narrated by David Attenborough:

Dr Richard Kirby is a British plankton expert, scientist, author and speaker. Follow Richard @planktonpundit on Twitter. You can see more images of plankton and learn more about them in Dr Richard Kirby’s book “Ocean Drifters, a secret world beneath the waves” available on Amazon and as an iBook.

Monday, 23 March 2015

View seafood differently using the hashtag #Wildlife4Sale

Over the coming weeks Blue Planet Society needs your help to highlight the availability of wild marine animals in supermarkets, fishmongers and fish markets across the globe by posting your photographs on social media using the hashtag #Wildlife4Sale.

Swordfish for sale in UK supermarket Iceland

Some people will have access to fish markets in tropical locations, others may only have their local shop. It doesn't have to be an exotic animal like a shark, marlin or swordfish, even the humble fish finger (fish stick) was once a wild animal.

Blue shark for sale at a market in Bournemouth, UK

So next time you go shopping, use your camera to show us which marine wildlife is for sale in your local area and post them on Twitter and Facebook using the hashtag #Wildlife4Sale.

At the end of the campaign Blue Planet Society will publish selected photographs to help expose the global trade in ocean wildlife and the threat it poses to the marine ecosystem.

Sunday, 23 November 2014

I’m a declining species, get me out of here

At a time when the Australian conservation movement faces great challenges, a protected seabird species in decline was consumed for novelty value on British reality TV show 'I’m A Celebrity...Get Me Out Of Here!' (Nov 22nd) in Murwillumbah, New South Wales.

Short-tailed shearwater, Tasman Sea, Australia. Pic: David Cook

Traditionally called “muttonbirds” by European settlers who exploited the birds for their oil, meat and feathers, the short-tailed shearwater has declined to less than a quarter of its original population, from 100 million to 23 million.

Short-tailed shearwaters are true “wanderers of the sea”, annually travelling tens of thousands of kilometres from feeding grounds in the Bering Sea to the southern coast of Australia, where the female lays her single egg in the southern spring. On arrival, they are literally starving and the east coast of Australia now regularly sees mass deaths of these birds, an occurrence which was previously seen only once in a decade.

Scientists are concerned that these events herald a much greater problem than storms, “This isn't just a freak event… This is obviously an indication of a much wider problem” said Seabird Biologist Jennifer Lavers of Monash University in 2013 when the worst wrecks occurred. Dismissing claims that weather events were responsible for the frequency of wrecks, Jennifer believes that it is the failure of the birds to locate fish that is the cause stating “Heavy winds will do great things to them, but is it just the wind? I would say no”.

Short-tailed shearwaters are protected in all states of Australia except for Tasmania, where up to 100,000 of the birds are commercially and recreationally hunted under licence. In recent times some areas have been forced to close their five week long season after only one week due to reports of decimated populations. Other threats to the short-tailed shearwater are climate change, pollution (oil spills and plastic consumption) and bycatch as the birds are frequently found following trawlers for a meal.

With this in mind, why are celebrities eating a rapidly declining IUCN listed and protected seabird on a reality TV show? In the past 'I'm A Celebrity' producers have been fined for cruelty to animals and criticised by well-known wildlife presenter Chris Packham who stated “killing animals for exploitative entertainment is unacceptable”, a statement echoed by the RSPCA. 'I'm A Celebrity' trivialises Australian wildlife for its shock value; snakes, crocodiles, insects and other animals have all been killed and eaten for entertainment.

With half of all wildlife lost since 1970, conservation should be at the forefront in the minds of the general public. This is unlikely to happen until producers of primetime TV shows like 'I'm A Celebrity' use their hugely influential platform to educate us about, not demean nature. It's the abused animals that should be taken out of this show, not the D-list celebrities.

Deborah Higgins is a Marine Biology student at Edith Cowan University, Western Australia and can be contacted at @Oceanwarrior on Twitter or Sea No Plastic on Facebook.

Thursday, 14 August 2014

Looming crisis: Five good reasons to avoid loom bands

Rainbow loom is a plastic loom used to weave colourful rubber bands into bracelets and charms. Loom bands are the latest must-have for kids, and the craze has gone global. Potentially this could have dire consequences for children's health, pets, wildlife and the environment.

1. Recent testing has found that loom bands can contain high levels of cancer-causing phthalates, which are hormone-disrupting chemicals used as softeners in the production of plastic.

2. Bright colours are often associated with food in nature. Marine animals could ingest loom bands and choke. Rubber bands have been known to get caught on the necks of animals and cause them to suffocate, or wrap around limbs and cause severe distress and ultimately death.

3. Loom bands have been eaten by household pets causing choking and resulting in costly vet bills.

4. Washed into drains and watercourses millions of lost loom bands pose a severe marine pollution threat.

Credit: Newquay Beachcoming

5. Loom bands cannot be recycled.

Sunday, 11 May 2014

Britain, please, no more balloon release events

Guillemot caught in a balloon. Pic: Balloons Blow

It should be common knowledge by now, mass balloon release events are bad for wildlife. But the message has yet to sink in, even with organisations that should know better.

According to the Marine Conservation Society "when balloons are released they don't just disappear. They float back down to earth where they are the same as any other litter. Balloons are mistaken for food by many species of wildlife. Once balloons have been eaten they can block the digestive system and cause animals to starve. The string on balloons can also entangle and trap animals".

Last year Blue Planet Society highlighted the threat posed by the 30,000 balloon release event held to celebrate Gibraltar National Day. Dialogue is ongoing but Gibraltar minister for culture Steven Linares has pledged to use only “environmentally-friendly, biodegradable balloons" which is great, except for one thing, no such balloons exist.

Even so-called biodegradable balloons hang around in the environment for long enough to cause real damage. In a test, Balloons Blow, an organisation that campaigns against balloon releases, placed biodegradable balloons in an outside environment and two years later they still hadn't decomposed.

In recent weeks social media campaigns have stopped mass balloon release events by life-saving charity RNLI, cruise line Cunard, retailer John Lewis and most recently the political party UKIP. A surprisingly irresponsible, unimaginative and crass event choice considering these organisations employ professional Marketing and PR resources to dream up ideas and advise on best practice.

To be fair, most organisations reacted very quickly and cancelled the event within hours of being asked. But they shouldn't have had to be asked. We're talking the very basics of environmental awareness here, and it's high time the message was heard. Balloons are bad for wildlife, bad for your company's image and a blight on the environment. So Britain, please, no more balloon release events.

Monday, 20 January 2014

Wild stingray encounter marred by reef fish decline

Smooth stingray waits to be fed. Pic: Blue Planet Society

Australia's south west offers a little-known wildlife experience that's hard to beat. At Hamelin Bay near Augusta huge wild smooth stingrays and eagle rays regularly come to the beach to be hand-fed by eager visitors.

Possibly unique in Australia, this behaviour began in the 1950s and 1960s when commercial fishermen cleaned their catch offshore. Today a fish-cleaning table for recreational anglers provides a seemingly endless supply of offcuts for the visiting rays.

Eagle ray (nearest) and smooth stingray. Pic: Blue Planet Society

For the marine conservationist this creates a dilemma. Many reef fish species caught by the anglers are in steep decline, so in the process of having a once-in-a-lifetime experience you may also be indirectly contributing to the ruination of Australia's offshore reef ecosystems.

Discarded juvenile western blue groper head.  Pic: Blue Planet Society

The overfishing of large reef fish has caused stocks to crash worldwide, and recreational angling is a significant contributing factor. Many reef fish species are long-lived, slow-growing and only present in relatively small numbers. Even moderate fishing pressure can have a dire effect. Add to this the lack of sufficient marine protected areas, inadequate fish stock assessments, and the outlook for fish like the western blue groper is bleak.

Stingray taking food from the hand of a tourist. Pic: Blue Planet Society

The rays themselves, which generate significant tourist income, have absolutely no legal protection. In January 2011 two young fishermen speared and butchered a tailless stingray nicknamed 'stumpy' in front of horrified onlookers. A plan to offer the rays more protection was drawn up in 2006 but is still awaiting approval. This lack of legal protection combined with the decline of reef ecosystems due to overfishing may see the end of the visiting rays and the priceless wildlife experience that they provide.

Hamelin Bay with angler boat ramp. Pic: Blue Planet Society