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For any bird, successfully raising chicks can be a tricky business, particularly for a ground-nesting bird such as the curlew (Numenius arquata), Europe’s largest wading bird. The curlew is listed as ‘near threatened’ by the IUCN and is a UK BAP (Biodiversity Action Plan) priority bird species due to the international importance of breeding and wintering UK populations, so when our Ecologist Martin Ledger found a curlew nest with eggs during a breeding birds survey, he documented what he saw. Following his second visit to the nest, he is still debating whether the eggs he originally found had successfully fledged or been predated, most likely by a hedgehog.

The evidence

On Martin’s first visit, he found a curlew nest hidden in the grass.

Location of curlew eggs

Location of curlew eggs

Inside the nest were four unhatched eggs. Curlews typically lay between three and six eggs, which are incubated for around a month before hatching.

Four unhatched curlew eggs

Four unhatched curlew eggs

Six days later, when Martin returned, he found the scene shown below: the eggs had either hatched or been predated. If predation was the reason for the broken egg shells, Martin believes that hedgehogs would be the prime suspect, as broken egg shells are a common trait when hedgehogs predate a nest, whilst other predators generally leave less mess.

Curlew egg shell remains

Curlew egg shell remains

However, finding egg shells and no chicks in the nest doesn’t necessarily mean the nest was predated. Curlews are usually precocial, meaning that the chicks generally leave the nest as soon as they are born and find food for themselves in thick cover, whilst they wait to develop their flying feathers. So the chicks could have hatched successfully and made a quick getaway!

The jury is still out on whether these curlew eggs hatched and fledged, but either way it has made for a lively debate and given us a further glimpse into the breeding life of a curlew.

The third Conference on Wind Energy and Wildlife Impacts was held at the Berlin Institute of Technology between March 10th and 12th, building on prior events in Stockholm (2013) and Trondheim (2011). The bi-annual event brings together representatives from academia, government agencies, industry, conservation and consultancies throughout the world. Over 400 delegates from around 30 countries attended, and Baker Consultants were represented by ornithological specialist Martin Ledger, and marine and ornithological specialist Rich Hall.

It was a busy few days, with more than 50 posters exhibited, 162 abstracts submitted, and 65 oral presentations across two parallel streams. Martin and Rich were not only able to absorb a lot of new thinking and fresh evidence on the subject of wildlife and wind energy, but also had the chance to speak to many of the most important stakeholders in the global industry, as well as fellow consultants and academics at the forefront of the drive to improve our understanding of how to maximise the environmental benefit of wind energy whilst minimising harmful effects on wildlife.

Conference on Wind Energy and Wildlife Impacts 2015

Conference on Wind Energy and Wildlife Impacts 2015

One of the biggest themes at the event was the call to vastly improve the data we feed into our collision risk assessments, especially with the increasing number of huge offshore wind farms across the world. So many studies have shown us that the most widely used models we have do not accurately predict the fatalities that occur at a given site. The industry as a whole needs to improve, and post-construction monitoring should become a fundamental part of this process, enabling us to properly assess, at a landscape scale, the most hazardous zones for wildlife, whether it be birds or bats, particularly with the increasing number of bats reported to be making huge and impressive migrations across the North Sea.

There was also new bioacoustics research and technology presented relating to effective mitigation during the initial establishment of wind farms and the noisy piling activities that affect fish, seals and cetaceans. This is an area in which Baker Consultants is already heavily involved, with recent projects in the North Sea, such as Borkum Riffgrund 1.

Martin and Rich intend to build on the information shared at this event and take it forward into their work, primarily across the UK and Europe, as part of this drive for better methods, better data, better mitigation and better assessment.