Will Climate Change cause Red Grouse Populations to suffer?

A twenty year study by the Game and Wildlife Conservation Trust (GWCT) shows that red grouse are laying eggs 0.5 days earlier each year, potentially harming their survival chances. As an endemic species, red grouse only exist in the British Isles, where they are an important game bird, and are managed due to loss of their heathland habitat.

The main concern earlier hatching raises for red grouse populations is trophic mismatch. This is where changes in population cycles occur, causing prey and predator species to be ‘out of sync’, with prey populations being lower than previously when predator populations are higher. Predator starvation or reduced survival prospects may result, as less food is available when needed. If red grouse chicks’ prey doesn’t coincide with chick hatching, the young red grouse may be left hungry. The warm weather seems to be driving craneflies – a key chick food – to be emerging even earlier than the chicks. This means even though chicks are hatching earlier, they may not be early enough for their prey and may still miss out. Even worse, early cranefly hatching can mean less survive to lay eggs for the following year.

Red grouse, Lagopus lagopus scotica - Alistair Young

Red grouse, Lagopus lagopus scotica, have been laying eggs earlier due to climate change. Image: Alistair Young.

As is often the case when climate change is considered, the effects on survival are even further complicated. The warmer springs produce more vegetation for red grouse hens to feed on, allowing them to produce more eggs. GWCT have found that hens laying earlier tend to have larger clutches, which could save the birds from decline.

As of yet, no overall effect on red grouse populations has been found.

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The birds and the bees in Hawaii: New study explore the effects of non-natives on ecosystem functioning

The more recent concept of monitoring restoration through ecosystem functioning has received support from scientists, but little practical study. New research by Hanna et al. (2012) studies the effects of invasive wasp species on plant pollination and fruiting in Hawaii.

Metrosideros polymorpha is an endemic flowering tree, historically pollinated by honeycreeper birds and bees. Honeycreepeer populations became threatened by predation from invasive spoecies, habitat degradation, competition and disease, causing population declines and extinctions. Following the decline of honeycreepers, and invasion of wasp species, Vespula pensylvanica, and introduction of the western honey bee, Apis mellifera, the non-native species began feeding on the nectar stores of M. polymorpha. V. pensylvanica is a non-pollinating insect; it reduces nectar availability to other wasps by defending a flower, where it stays, drinking the nectar and chasing away or hunting and eating pollinating bees. This reduces the plants fruiting success, as the wasp reduces the nectar supplies M. polymorpha produces to attract pollinators, and directly repels other insects, preventing pollination. A. mellifera, however, is known to pollinate some plants, though only those whose flower shape enables pollination transfer from the small honey bee.

Hanna et al. experimentally removed V. pensylvanica from selected sites, and recorded the effects on pollinaters and fruiting success. Visitation by pollinating insects increased, likely as predation risk decreased and nectar more available, which led to increased fruiting success. Both A. mellifera and endemic Hylaeus began visiting the flowers more often, but Hanna et al. believe they had differing effects on fruiting success. As A. mellifera visited more frequently, it would appear that they are more responsible for the increased fruiting success than Hylaeus, whose visitation rates increased less. A. mellifera could be acting as replacement pollinators following the drop in honeycreeper numbers, helping to sustain plant fruiting. Though this effect is postive for M. polymorpha, an increase in A. mellifera could increase competition with other pollinators, and may not be an effective pollinator of all plant species from which it takes nectar, especially ones which attract a less diverse range of pollinators.

This study emphasises the need to assess how species alter ecosystem functioning when forming management plans, and highlights the variability of impacts of invasive species. Hanna et al. suggest the next steps taken should be to assess wider effects of A. mellifera, and how V. penslyvanica affects pollination at different times of the season.

Hanna, C., Foote, D., Kremen, C. (2012), Invasive species management restores a plant–pollinator mutualism in Hawaii. Journal of Applied Ecology.

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Modern Fishing: using science to set tuna quota regulations

For decades overfishing has been a major concern, but new tuna quotas utilise scientists’ recommendations to achieve a sustainable fishing effort. Despite recent tuna increases, The International Commission for the Conservation of Atlantic Tunas (ICCAT), who set tuna fishing regulations, decided to set only a small increase in tuna fishing quotas, to allow population recovery.

Many tuna species have shown decreased populations as a direct result of overfishing, such as the bluefin tuna, which fell by 60% between 1997 and 2007. These declines, their high market demand, and the negative effects of tuna fishing on other species were cause for quota implementation. Recent evidence suggests a rebounding of tuna populations, but scientists warn that caution must be used when adjusting regulations, due to their still low numbers and fragile state. Concern over the long-term sustainability of conservation action has been previously raised, with scientists stressing the need to allow recovery from depleted states even when populations are increasing.

With pressure exerted on regulatory bodies by fisheries, the proper use of science when setting fishing limits has often been previously ignored. The relatively low increase in ICCAT 2013 quotas, however, helps break this trend by including science in policy-making. Such action helps guide the way towards more informed and sustainable marine use.

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One fifth of invertebrates at risk, finds new research

One fifth of all invertebrates are now considered threatened by extinction according to a report published by the Zoological Society of London last week.  As a category invertebrates are of great significance – ranging from insects to jellyfish, they make up approximately 98% of all animal species. 

Bolinopsis infundibulum, a carnivorous and phosphorescent comb jelly, NOAA

The study looked at over 12,000 species, and was completed in conjunction with the IUCN. The accuracy of the findings have been questioned by some due to the small sample size used; about 1 million invertebrate species are currently known, and studies suggest only 14% of  species have been discovered. 
As the first study of its kind, however, the report helps to give an overall idea of the status of a group that comprises almost all of Earths animals. Freshwater species were found to be particularly vulnerable, as were less mobile species. The trends revealed by these disparities will assist scientists in targeting species and areas of particular concern. Habitat loss, pollution and invasive species were listed as the top threats to species survival. Although these factors have been the subject of much concern already, clarifying their level of threat helps to form a scientific basis for future action. The results are similar to those of studies on vertebrates and plants, which also found a fifth of species to be at risk.

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Silent Spring celebrates its 50th anniversary

In contrast to the care-free, all-loving vibe often associated with the Sixties, Silent Spring stood as a confrontational and alarming reality hit of the choking effects of industry on nature. This year marks the 50th anniversary of Carson’s Silent Spring, which has been described as ‘one of the most important books in ecology’ and helped bring environmental issues into the public eye at a time when awareness was low but destruction high.

Silent Spring focuses on the disastrous effects of pesticides on the environment. The title alludes to the detrimental effects of chemicals such as DDT on animals – in particular birds – due to bioaccumulation and unforeseen side-effects.

Carson became interested in the release of such chemicals into the environment as early as the 1940’s, but states that the impetus for the book came from a letter in a local newspaper, reporting numerous bird deaths following a DDT spraying. It was this, along with Carson’s background as a marine biologist and experience as a published author that led to the writing of Silent Spring.

Seen by many as a subversive and damaging notion, the message delivered by Carson’s account was met with threats of lawsuits and accusations of exaggeration. Her claims sparked an investigation by then-US President Kennedy, which led to the tightening of pesticide regulations and a surge in public interest in pollution and environmental protection.

Today, Silent Spring stands as a prominent historical publication for conservationists. Carson’s writing is direct and steadfast, yet accessible, helping inspire mass environmental movement against issues once controversial and little-known.

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Wind turbines are notorious bird-killers, so why are the RSPB building one?

Clashes between bird conservationists and wind farm supporters first arose in the early eighties, when deaths by collision blackmarked the sustainable energy ‘solution’ as a major threat to larger bird species. Species most at risk are be birds of prey and waterbirds, both of which are more likely to die from collisions, and have lower population growth rates and poorer manoeuvrability in flight. Bird charities such as the RSPB have since campaigned against many wind farm proposals, so why are they now building a turbine in their own headquarters?

Barnacle goose, Branta leucopsis, are particularly vulnerable to collisions

 Since the first wind farms were designed, much effort has been ploughed into reducing their impacts on nature. Whilst deaths of larger bird species are concerning, the RSPB has only objected to around six percent of wind farm applications across the country – the main cause of concern being migration routes.

It is still true that turbines cause fatalities, however studies have shown that, for every bird killed by wind farms, 5820 are killed by striking buildings. The RSPB stress that it is still important to monitor the risk of turbines, and appropriate precautions should be employed – locations away from populations of endangered species should be preferred, and those away from migration routes. Set to arise in Autumn 2013, the RSPB turbine will provide over two thirds of the RSPB’s electricity usage across the UK from its location in Bedfordshire. It will stand as a statement that wind energy, when harnessed appropriately, can be a useful tool in fighting climate change and providing a sustainable future.

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Australia’s controversial Coral Sea reserve divides critics

Plans to create a marine reserve that will become the largest protected area in the world have been announced by Australian officials last week, with controversy already rising about its motives and success.

The reserve will cover 3.1 sq km, enclosing the Coral Sea and Great Barrier Reef, areas of significant biodiversity. In the current context of marine protection, which is notoriously lacking, decisions to create the reserve should be highly commended, but closer examination has divided opinions of environmentalists and politicians.

Coral Outcrop at Flynn Reef, Great Barrier Reef – Toby Hudson

Restrictions on fishing, a major cause of conservation concern globally, have been estimated to cost the industry 36,000 jobs; compensation of 100m AUD has been suggested by Australia’s Environmental Minister. Whilst the fishing industry may resent the reserve plans, environmentalists have been quick to point out that 80% of the reserve will be open to fishing, two thirds of which may be commercial.

Oil and gas exploration is another issue. Burke declares the reserve to be “leading that next step [in protecting our oceans]”, but others claim the design to be heavily influenced by appeasing Australia’s oil and gas industries. A significant North-west region, where energy exploration has already been developed, has been left vulnerable, as are many lucrative patches around the framework.

With many conflicting interests to consider, such plans were certain to cause contention, but risk angering those concerned when sincerity and loyalty becomes questioned.

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