Great skua (Stercorarius skua) movements at sea in relation to marine renewable energy developments.

Marine renewable energy developments (MREDs) are an increasing feature of the marine environment. Owing to the relatively small number of existing developments and the early stage of their associated environmental monitoring programmes, the effects of MREDs on seabirds are not fully known. Our ability to fully predict potential effects is limited by a lack of knowledge regarding movements of seabirds at sea. We used GPS tracking to improve our understanding of the movements at sea of a protected seabird species breeding in Scotland, the great skua (Stercorarius skua), to better predict how this species may be affected by MREDs. We found that the overlap of great skuas with leased and proposed MREDs was low; particularly with offshore wind sites, which are predicted to present a greater risk to great skuas than wave or tidal-stream developments. Failed breeders overlapped with larger areas of MREDs than breeding birds but the overall overlap with core areas used remained low. Overlap with wave energy development sites was greater than for offshore wind and tidal-stream sites. Comparison of 2011 data with historical data indicates that distances travelled by great skuas have likely increased over recent decades. This suggests that basing marine spatial planning decisions on short-term tracking data could be less informative than longer-term data.

mild Interlaminar decompression for the treatment of lumbar spinal stenosis: procedure description and case series with 1-year follow-up.

OBJECTIVES: mild interlaminar decompression is a minimally invasive procedure for the treatment of patients with symptomatic lumbar spinal stenosis. This report describes the mild procedure and presents 1-year clinical outcomes of patients treated with mild. METHODS: mild treats lumbar spinal stenosis by removing portions of the lamina and ligamentum flavum to restore space in the lumbar spine. The procedure is conducted under fluoroscopic guidance, and is performed with moderate sedation. One-year follow-up was obtained for 17 patients treated with the mild procedure. Clinical evaluations were conducted at baseline and at 1-year follow-up with the 10-point Visual Analog Score and Oswestry Disability Index. RESULTS: mild treatments were completed with no major device-related or procedure-related complications. The baseline mean Visual Analog Score of 7.6 improved at 1 year after the procedure to 2.3, a decrease of 5.4 cm points, or an average percentage decrease of 70.0%. Average baseline Oswestry Disability Index of 48.4 improved to 21.7 at 1 year, an improvement of 26.6 points. DISCUSSION: The mild technique provides an attractive early option for the treatment of symptomatic lumbar spinal stenosis after failed injection therapy, but before more invasive surgical treatment. For 17 patients with 1-year follow-up, the mild procedure provided significant pain relief and increased mobility. This procedure leaves no implants behind, and therefore does not limit subsequent, more invasive procedures that require implants.

The value of constant surveillance in a risky environment.

In risky environments, where threats are unpredictable and the quality of information about threats is variable, all individuals face two fundamental challenges: balancing vigilance against other activities, and determining when to respond to warning signals. The solution to both is to obtain continuous estimates of background risk, enabling vigilance to be concentrated during the riskiest periods and informing about the likely cost of ignoring warnings. Human surveillance organizations routinely produce such estimates, frequently derived from indirect cues. Here we show that vigilant individuals in an animal society (the pied babbler, Turdoides bicolor) perform a similar role. We ask (i) whether, in the absence of direct predator threats, pied babbler sentinels react to indirect information associated with increased risk and whether they communicate this information to group mates; (ii) whether group mates use this information to adjust their own vigilance, and whether this influences foraging success; and (iii) whether information provided by sentinels reduces the likelihood of inappropriate responses to alarm calls. Using playback experiments, we show that: (i) sentinels reacted to indirect predator cues (in the form of heterospecific alarm calls) by giving graded surveillance calls; (ii) foragers adjusted their vigilance in reaction to changes in surveillance calls, with substantial effects on foraging success; and (iii) foragers reduced their probability of responding to alarm calls when surveillance calls indicated lowered risk. These results demonstrate that identifying attacks as they occur is only part of vigilance: equally important is continuous surveillance providing information necessary for individuals to make decisions about their own vigilance and evasive action. Moreover, they suggest that a major benefit of group living is not only the increased likelihood of detecting threats, but a marked improvement in the quality of information available to each individual.