As Arctic ship traffic increases, narwhals and other unique animals are at risk


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A pod of narwhals (Monodon monoceros) in central Baffin Bay. Narwhals are the most vulnerable animals to increased ship traffic in the Arctic Ocean.
Kristin Laidre/University of Washington, CC BY-ND

Donna Hauser, University of Alaska Fairbanks; Harry Stern, University of Washington, and Kristin Laidre, University of Washington

Most Americans associate fall with football and raking leaves, but in the Arctic this season is about ice. Every year, floating sea ice in the Arctic thins and melts in spring and summer, then thickens and expands in fall and winter.

As climate change warms the Arctic, its sea ice cover is declining. This year scientists estimate that the Arctic sea ice minimum in late September covered 1.77 million square miles (4.59 million square kilometers), tying the sixth lowest summertime minimum on record.

With less sea ice, there is burgeoning interest in shipping and other commercial activity throughout the Northwest Passage – the fabled route that links the Atlantic and Pacific oceans, via Canada’s convoluted Arctic archipelago – as well as the Northern Sea Route, which cuts across Russia’s northern seas. This trend has serious potential impacts for Arctic sea life.

In a recent study, we assessed the vulnerability of 80 populations of Arctic marine mammals during the “open-water” period of September, when sea ice is at its minimum extent. We wanted to understand the relative risks of vessel traffic across Arctic marine mammal species, populations and regions. We found that more than half (53 percent) of these populations – including walruses and several types of whales – would be exposed to vessels in Arctic sea routes. This could lead to collisions, noise disturbance or changes in the animals’ behavior.

Map of the Arctic region showing the the Northern Sea Route and Northwest Passage.
Arctic Council/Susie Harder

Less ice, more ships

More than a century ago, Norwegian explorer Roald Amundsen became the first European to navigate the entire Northwest Passage. Due to the short Arctic summer, it took Amundsen’s 70-foot wooden sailing ship three years to make the journey, wintering in protected harbors.

Fast-forward to summer 2016, when a cruise ship carrying more than 1,000 passengers negotiated the Northwest Passage in 32 days. The summer “open-water” period in the Arctic has now increased by more than two months in some regions. Summer sea ice cover has shrunk by over 30 percent since satellites started regular monitoring in 1979.

Bowhead whale (Balaena mysticetus) in Disko Bay, West Greenland.
Kristin Laidre, CC BY

Arctic seas are home to a specialized group of marine mammals found nowhere else on Earth, including beluga and bowhead whales, narwhals, walruses, ringed and bearded seals and polar bears. These species are critical members of Arctic marine ecosystems, and provide traditional resources to Indigenous communities across the Arctic.

According to ecologists, all of these animals are susceptible to sea ice loss. Research at lower latitudes has also shown that marine mammals can be affected by noise from vessels because of their reliance on sound, as well as by ship strikes. These findings raise concerns about increasing vessel traffic in the Arctic.

Ringed seal (Pusa hispida) pup in Alaska.
NOAA

Sensitivity times exposure equals vulnerability

To determine which species could be at risk, we estimated two key factors: Exposure – how much a population’s distribution overlaps with the Northwest Passage or Northern Sea Route during September – and sensitivity, a combination of biological, ecological and vessel factors that may put a population at a higher risk.

As an illustration, imagine calculating vulnerability to air pollution. People generally are more exposed to air pollution in cities than in rural areas. Some groups, such as children and the elderly, are also more sensitive because their lungs are not as strong as those of average adults.

We found that many whale and walrus populations were both highly exposed and sensitive to vessels during the open-water period. Narwhals – medium-sized toothed whales with a large spiral tusk – scored as most vulnerable overall. These animals are endemic to the Arctic, and spend much of their time in winter and spring in areas with heavy concentrations of sea ice. In our study, they ranked as both highly exposed and highly sensitive to vessel effects in September.

Narwhals have a relatively restricted range. Each summer they migrate to the same areas in the Canadian high Arctic and around Greenland. In fall they migrate south in pods to offshore areas in Baffin Bay and Davis Strait, where they spend the winter making deep dives under the dense ice to feed on Greenland halibut. Many narwhal populations’ core summer and fall habitat is right in the middle of the Northwest Passage.

A pod of narwhals (Monodon monoceros) in central Baffin Bay. Narwhals are the most vulnerable animals to increased ship traffic in the Arctic during September.
NOAA/OAR/OER/Kristin Laidre

Vulnerable Arctic regions, species and key uncertainties

The western end of the Northwest Passage and the eastern end of the Northern Sea Route converge at the Bering Strait, a 50-mile-wide waterway separating Russia and Alaska. This area is also a key migratory corridor for thousands of beluga and bowhead whales, Pacific walruses and ringed and bearded seals. In this geographic bottleneck and other narrow channels, marine mammals are particularly vulnerable to vessel traffic.

Among the species we assessed, polar bears were least vulnerable to September vessel traffic because they generally spend the ice-free season on land. Of course, longer ice-free seasons are also bad for polar bears, which need sea ice as a platform for hunting seals. They may also be vulnerable to oil spills year-round.

Research in the harsh and remote Arctic seas is notoriously difficult, and there are many gaps in our knowledge. Certain areas, such as the Russian Arctic, are less studied. Data are sparse on many marine mammals, especially ringed and bearded seals. These factors increased the uncertainty in our vessel vulnerability scores.

We concentrated on late summer, when vessel traffic is expected to be greatest due to reduced ice cover. However, ice-strengthened vessels can also operate during spring, with potential impacts on seals and polar bears that are less vulnerable in September. The window of opportunity for navigation is growing as sea ice break-up happens earlier in the year and freeze-up occurs later. These changes also shift the times and places where marine mammals could be exposed to vessels.

The Arctic Ocean is covered with floating sea ice in winter, but the area of sea ice in late summer has decreased more than 30 percent since 1979. The Arctic Ocean is projected to be ice-free in summer within decades.

Planning for a navigable Arctic

Recent initiatives in the lower 48 states offer some models for anticipating and managing vessel-marine mammal interactions. One recent study showed that modeling could be used to predict blue whale locations off the California coast to help ships avoid key habitats. And since 2008, federal regulations have imposed seasonal and speed restrictions on ships in the North Atlantic to minimize threats to critically endangered right whales. These practical examples, along with our vulnerability ranking, could provide a foundation for similar steps to protect marine mammals in the Arctic.

The International Maritime Organization has already adopted a Polar Code, which was developed to promote safe ship travel in polar waters. It recommends identifying areas of ecological importance, but does not currently include direct strategies to designate important habitats or reduce vessel effects on marine mammals, although the organization has taken steps to protect marine habitat in the Bering Sea.

Even if nations take rigorous action to mitigate climate change, models predict that September Arctic sea ice will continue to decrease over the next 30 years. There is an opportunity now to plan for an increasingly accessible and rapidly changing Arctic, and to minimize risks to creatures that are found nowhere else on Earth.The Conversation

Donna Hauser, Research Assistant Professor, International Arctic Research Center, University of Alaska Fairbanks; Harry Stern, Principal Mathematician, Polar Science Center, University of Washington, and Kristin Laidre, Associate Professor of Aquatic and Fishery Sciences, University of Washington

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Climate change will make QLD’s ecosystems unrecognisable – it’s up to us if we want to stop that



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It’s not just about the Great Barrier Reef. Queensland’s rainforests – particularly in the mountains – will also change thanks to a warming climate.
Shutterstock

Sarah Boulter, Griffith University

Climate change and those whose job it is to talk about current and future climate impacts are often classed as the “harbingers of doom”. For the world’s biodiversity, the predictions are grim – loss of species, loss of pollination, dying coral reefs.

The reality is that without human intervention, ecosystems will reshape themselves in response to climate change, what we can think of as “autonomous adaptation”. For us humans – we need to decide if we need or want to change that course.

For those who look after natural systems, our job description has changed. Until now we have scrambled to protect or restore what we could fairly confidently consider to be “natural”. Under climate change knowing what that should look like is hard to decide.

If the Great Barrier Reef still has a few pretty fish and coral in the future, and only scientists know they are different species to the past, does that matter? It’s an extreme example, but it is a good analogy for the types of decisions we might need to make.




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In Queensland, the government has just launched the Biodiversity and Ecosystem Climate Adaptation Plan for Queensland focused on what is considered important for making these decisions. The plan is high level, but is an important first step toward preparing the sector for the future.

Changing ecosystems

For the rest of Queensland’s ecosystems the story is much the same as the Great Barrier Reef. There are the obvious regions at risk. Our coastal floodplains and wetlands are potentially under threat from both sides, with housing and development making a landward march and the sea pushing in from the other side. These ecosystems literally have nowhere to go in the crush.

It’s a similar story for species and ecosystems that specialise on cool, high altitude mountaintops. These small, isolated populations rely on cool conditions. As the temperature warms, if they can’t change their behaviour (for instance, by taking refuge in cool spots or crevices during hot times), then it is unlikely they will survive without human intervention such as translocation.




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Climate change could empty wildlife from Australia’s rainforests


We are all too familiar with the risk of coral reefs dying and becoming a habitat for algae, but some of our less high profile ecosystems face similar transformations. Our tropical savannah woodlands cover much of the top third of Queensland. An iconic ecosystem of the north, massive weed invasions and highly altered fire regimes might threaten to make them unrecognisable.

Changing fire patterns and invasive species could see dramatic changes in Queensland’s savannah woodlands.
Shutterstock

So where to from here?

From the grim predictions we must rally to find a way forward. Critically for those who must manage our natural areas it’s about thinking about what we want to get out of our efforts.

Conservation property owners, both public (for instance, national parks) and private (for instance, not-for-profit conservation groups), must decide what their resources can achieve. Throwing money at a species we cannot save under climate change may be better replaced by focusing on making sure we have species diversity or water quality. It’s a hard reality to swallow, but pragmatism is part of the climate change equation.

We led the development of the Queensland plan, and were encouraged to discover a sector that had a great deal of knowledge, experience and willingness. The challenge for the Queensland government is to usefully channel that energy into tackling the problem.

Valuing biodiversity

One of the clearest messages from many of the people we spoke to was about how biodiversity and ecosystems are valued by the wider community. Or not. There was a clear sense that we need to make biodiversity and ecosystems a priority.

The Great Barrier Reef is already seeing major climate impacts, particularly bleaching.
Shutterstock

It’s easy to categorise biodiversity and conservation as a “green” issue. But aside from the intrinsic value or personal health and recreation value that most of us place on natural areas, without biodiversity we risk losing things other than a good fishing spot.

Every farmer knows the importance of clean water and fertile soil to their economic prosperity. But when our cities bulge, or property is in danger from fire, we prioritise short-term economic returns, more houses or reducing fire risk over biodiversity almost every time.

Of course, this is not to say the balance should be flipped, but climate change is challenging our politicians, planners and us as the Queensland community to take responsibility for the effects our choices have on our biodiversity and ecosystems. As the pressure increases to adapt in other sectors, we should seek options that could help – rather than hinder – adaptation in natural systems.

Coastal residences may feel that investing in a seawall to protect their homes from rising sea levels is worthwhile even if it means sacrificing a scrap of coastal wetland, but there are opportunities to satisfy both human needs and biodiversity needs. We hope the Queensland plan can help promote those opportunities.

Cath Moran contributed to developing this article.The Conversation

Sarah Boulter, Research Fellow, National Climate Change Adaptation Research Facility, Griffith University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

How we wiped out the invasive African big-headed ant from Lord Howe Island



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Not welcome: the African big headed ant might be small but it can be a pest if it gets in your home.
CSIRO, Author provided

Ben Hoffman, CSIRO

The invasive African big-headed ant (Pheidole megacephala) was found on Lord Howe Island in 2003 following complaints from residents about large numbers of ants in buildings.

But we’ve managed to eradicate the ant completely from the island using a targeted mapping and baiting technique than can be used against other invasive species.

Up to 15% of Lord Howe Island was thought to be infested with the ant.
CSIRO, Author provided

A major pest

The African big-headed ant is one of the world’s worst invasive species because of its ability to displace some native plants and wildlife, and adversely affect agricultural production.




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It’s also a serious domestic nuisance. People can become overwhelmed by the large number of ants living in their buildings – you can’t leave a bit of food lying around, especially pet food, or it will be covered in ants.

It remains unclear how long the ant had been on Lord Howe Island, in the Tasman Sea about 770 km northeast of Sydney, before being found. But it is likely to have been present for at least a decade.

Because of the significant threat this ant posed to the conservation integrity of the island, an eradication program was started. But on-ground work done from 2003 to 2011 had many failings and was not working.

In 2011, I was brought in to oversee the program. The last ant colony was killed in 2016, but it is only now, two years later, that we are declaring Lord Howe Island free from the ants.

No African big-headed ants have been seen on the island for two years.
CSIRO, Author provided

A super colony

The ability to eradicate this ant is largely due to its relatively unique social organisation. The queens don’t fly to new locations to start new nests – instead, they form interconnected colonies that can extend over large areas.

This makes the ant’s distribution easy to map and treat. The ant requires human assistance for long-distance transport, so the ant will only be found in predictable locations where it can be accidentally transported by people.

From 2012 to 2015, all locations on the island where the ant was likely to be present were formally inspected. Priority was given to places where an infestation was previously recorded or considered likely. The populations were mapped, and then treated using a granular bait available at shops.

In the latter years we found 16 populations covering 30 hectares. Limited by poor mapping in the early years, we estimate that the ant originally covered up to 55 hectares, roughly 15% of the island.

Stopping the spread

The widespread distribution of the ant through the populated area of the island is thought to have been aided by the movement of infested mulch and other materials from the island’s Waste Management Facility.

To prevent any more spread of the ant, movement restrictions were imposed in 2003 on the collection of green waste, building materials and other high risk items from the facility.

The baiting program used a product that contains a very low dose of insecticide that has an extremely low toxicity to terrestrial vertebrates such as pet cats and dogs, birds, lizard etc. The toxicant rapidly breaks down into harmless chemicals after exposure to light.

No negative impacts were recorded on any of the native wildlife on the island.

Importantly, the African ant usually kills most other ants and other invertebrates where it is present, so there are few invertebrates present to be affected by the bait.

Ecological recovery of the infested areas was rapid following baiting and the eradication of the African ant.

Another ant invader

One of the main challenges was getting the ground crew to correctly identify the ant.

It turns out there was a second (un-named) big-headed ant species present, also not native to the island, that created a lot of unnecessary work being conducted where the African ant wasn’t present.

CSIRO and Lord Howe Island Board team tackling the African big headed ant problem.
CSIRO, Author provided

Like numerous other exotic ant species present, this second species was of no environmental or social concern, so there are no plans to manage or eradicate it.

The protocols used in this program are essentially the same that are being used in other eradication programs against Electric ant in Cairns and Browsing ant in Darwin and Perth, because those two species also create supercolonies.




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It is highly likely that those programs will also achieve eradication of their respective species, the first instance where an ant species has been eradicated entirely from Australia.

The fire ant program in Brisbane has many similarities, but there are distinct differences in that the ants there don’t form supercolonies that are so easy to map, and the area involved is far greater.The Conversation

Ben Hoffman, Principal research scientist, CSIRO

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Drugs in bugs: 69 pharmaceuticals found in invertebrates living in Melbourne’s streams



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Thanks to their consumption of invertebrates, Melbourne platypus likely receive half the recommended human dose of anti-depressants every day.
Denise Illing

Erinn Richmond, Monash University and Mike Grace, Monash University

Pharmaceuticals from wastewater are making their way into aquatic invertebrates and spiders living in and next to Melbourne’s creeks, according to our study published today in Nature Communications.

We found pharmaceuticals in every bug we sampled – over 190 invertebrates – from six different streams. These included caddisfly larvae, midge larvae, snails and dragonfly larvae. We also found pharmaceuticals in spiders living in stream-side vegetation.

We found 69 different drugs in the bugs, including fluoxetine and mianserin (anti-depressants), fluconazole (an anti-fungal), and non-steroidal anti-inflamatories (NSAIDs), often used to treat arthritis.

While we don’t know how these drugs are affecting these invertebrates, we know from other studies pharmaceuticals do affect the lifecycles of other organisms.

We also calculated that animals that eat these aquatic invertebrates, such as platypus, would be receiving half the daily recommended dose of anti-depressants for humans.




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Drugs everywhere

We know wastewater is a contributing factor to pharmaceutical contamination in aquatic organisms, so we sampled from a range of streams with different wastewater inputs. These included a site just downstream of large-scale wastewater treatment facility, and areas with ageing septic systems.

Sassafrass Creek, one of the streams sampled in the study.
Erinn Richmond

We also included a stream within a national park to attempt to obtain samples we thought would be free of pharmaceuticals. We sampled aquatic invertebrates and stream-side spiders and tested them for 98 pharmaceutical compounds.

To our surprise, we found up to 69 different pharmaceuticals in aquatic invertebrates and up to 66 in riparian (streamside) spiders. Contamination was greatest downstream of the high capacity waste water treatment plant.

Moreover, every insect we sampled contained pharmaceuticals, including at the site in a national park, possibly due to septic systems in the drainage area of the stream that contribute small amounts of waste water.

The fact we detected drugs, admittedly in very low concentrations, in this seemingly pristine site suggests finding places “free” from pharmaceutical contamination may be difficult. Recent studies by other researchers detected pharmaceutical contamination in surface water in Antarctica and in national parks in the US.

We also found spiders living on the stream edge (the “riparian zone”), also contain a wide variety of pharmaceuticals in their tissues. These animals primarily consume adult insects and are an indication other animals that eat adult aquatic insects, such as birds, reptiles and bats, may also be exposed.

Spiders living in stream-side vegetation take up pharmaceuticals from the insects they eat.
Erinn Richmond

The dark side of our pharmaceutical use

We take and are prescribed pharmaceuticals to improve our quality of life. These medications are designed to be biologically active – they are meant to treat us; for example, we take paracetamol to alleviate a headache. For all the benefits drugs afford us, there is an often overlooked dark side to our extensive use of them.




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When we take a pharmaceutical, our bodies do not always use all of the drug and we excrete drug residues into our waste water and the drugs then move into our sewage system. Unfortunately, waste water treatment facilities are not always designed to, or are capable of, removing pharmaceuticals. So they’re often discharged into our streams, rivers and coastal waters.

Lead author, Erinn, sampling invertebrates in Brushby Creek.
Keralee Brown

We have known from many studies over almost two decades that the drugs we take are found in waterways around the world. There are thousands of drugs available, but very little is known about their occurrence and movement through aquatic food webs.

Our research team has previously studied the effects these pharmaceuticals have on organisms living in streams. For example, we found fluoxetine, a common anti-depressant, increased stream insect emergence (the important phase of an insects’ life where it metamorphoses from a stream dwelling larvae to an aerial adult).

We also found this antidepressant, and other drugs, alter the rates of photosynthesis in algae, the important base of stream food webs.

Happy platypus?

Platypus and trout live in or nearby the streams we studied. These animals feed almost exclusively on aquatic invertebrates. Although we did not directly sample trout or platypus, we were able to use previous studies on the feeding rates of these animals to estimate what proportion of a human daily dose of drugs they may be exposed just by eating the aquatic invertebrates we did measure in the streams we studied.

Based on these calculations, a platypus living in a creek receiving waste water could be exposed to over half of a human daily dose (per kg body weight) of antidepressants, just by eating aquatic invertebrates. Trout, too, would be exposed to these drugs, but would be exposed to a lower dose.

Studies have shown single drugs can alter the behaviour of fish, but just what consuming 69 different pharmaceutical compounds might do to a fish or platypus remains unknown and worthy of future research.

Global pharmaceutical use is increasing, with many benefits to humankind. However, our recent publication makes it clear pharmaceuticals are accumulating and moving through stream food webs and expose spiders, and likely birds, bats, fish, and platypus to a wide array of drugs. We are yet to fully understand the broader ecological consequences of this type of pharmaceutical contamination.

We know in humans, there are health risks associated with taking multiple drugs because of drug interactions. Is the same true for animals? Like so many studies, our research leaves us with many unanswered questions.

The one thing that is abundantly clear is the drugs we so frequently use are ending up in nature and are moving through food webs.

This article was co-authored by Emma Rosi, an aquatic ecologist at the Cary Institute of Ecosystem Studies.The Conversation

Erinn Richmond, Research Fellow, School of Chemistry, Monash University and Mike Grace, Associate Professor, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.