Herbivorous dietary selection shown by hawfinch (Coccothraustes coccothraustes) within mixed woodland habitats.

Knowledge of diet and dietary selectivity is vital, especially for the conservation of declining species. Accurately obtaining this information, however, is difficult, especially if the study species feeds on a wide range of food items within heterogeneous and inaccessible environments, such as the tree canopy. Hawfinches (Coccothraustes coccothraustes), like many woodland birds, are declining for reasons that are unclear. We investigated the possible role that dietary selection may have in these declines in the UK. Here, we used a combination of high-throughput sequencing of 261 hawfinch faecal samples assessed against tree occurrence data from quadrats sampled in three hawfinch population strongholds in the UK to test for evidence of selective foraging. This revealed that hawfinches show selective feeding and consume certain tree genera disproportionally to availability. Positive selection was shown for beech (Fagus), cherry (Prunus), hornbeam (Carpinus), maples (Acer) and oak (Quercus), while Hawfinch avoided ash (Fraxinus), birch (Betula), chestnut (Castanea), fir (Abies), hazel (Corylus), rowan (Sorbus) and lime (Tilia). This approach provided detailed information on hawfinch dietary choice and may be used to predict the effects of changing food resources on other declining passerines populations in the future.

Multi-marker DNA metabarcoding reveals spatial and sexual variation in the diet of a scarce woodland bird.

Avian diet can be affected by site-specific variables, such as habitat, as well as intrinsic factors such as sex. This can lead to dietary niche separation, which reduces competition between individuals, as well as impacting how well avian species can adapt to environmental variation. Estimating dietary niche separation is challenging, due largely to difficulties in accurately identifying food taxa consumed. Consequently, there is limited knowledge of the diets of woodland bird species, many of which are undergoing serious population declines. Here, we show the effectiveness of multi-marker fecal metabarcoding to provide in-depth dietary analysis of a declining passerine in the UK, the Hawfinch (Coccothraustes coccothraustes). We collected fecal samples from (n = 262) UK Hawfinches prior to, and during, the breeding seasons in 2016-2019. We detected 49 and 90 plant and invertebrate taxa, respectively. We found Hawfinch diet varied spatially, as well as between sexes, indicating broad dietary plasticity and the ability of Hawfinches to utilize multiple resources within their foraging environments.

Impact of woodland agri-environment management on woodland structure and target bird species.

Agri-environment incentives form a central mechanism supporting changes to land management to provide public benefits. This study assesses the medium-term effects of woodland management on 13 target, specialist woodland bird species, as well as other woodland birds in a single region of the UK. The abundance of breeding birds (using two methods: point counts and territory mapping) and metrics of woodland structure were recorded on sites with Woodland Improvement Grants (improvement sites) and nearby comparison sites (control sites). Initial measurements were made prior to management and repeated 7-9 years later. A separate comparison of changes in bird abundance was made between the managed woodland sites and woodland from similar landscapes surveyed as part of the national Breeding Bird Survey (BBS). There was an increase in abundance of target species on improvement sites compared to a decrease on both control sites and BBS sites, although this was only evident from point count data. The effects on target species were stronger than for other woodland specialists and there was no apparent effect on woodland generalists, suggesting that the management interventions were appropriate for the target species. Changes in woodland structure were generally consistent with the expected effect of management, with lower tree density and greater Bramble (Rubus sp.) cover. However, contrary to the aim of increasing understorey cover, a reduction was recorded within the 2-10 m height category in improvement sites. This contrast is due to the removal of young trees during thinning affecting this height band and the short time period since management to allow regrowth. Our findings show that bespoke management supported through government agri-environment incentives can have a positive impact on target woodland birds. For managed forests, identifying species requirements and how management can be adapted to improve their habitats can be an effective way of delivering biodiversity gains when financial incentives are provided to achieve policy goals.

Heparin prophylaxis and the risk of venous thromboembolism after robotic-assisted laparoscopic prostatectomy.

OBJECTIVE: • The incidence of venous thromboembolism (VTE) after robotic-assisted laparoscopic prostatectomy (RALP) in patients receiving perioperative heparin prophylaxis was compared with those who did not receive such prophylaxis. MATERIALS AND METHODS: • Between July 2007 to February 2010, a total of 307 RALPs were performed at our institution by two surgeons. A total of 187 patients operated on by surgeon 1 received perioperative heparin prophylaxis, whereas 120 patients operated on by surgeon 2 did not receive any. • All demographic, clinical and pathological data were prospectively recorded, whereas the incidence of venous thromboembolism within 30 days of the operation was retrospectively reviewed. Evaluation for potential VTE was based on clinical symptoms. RESULTS: • Cohorts were comparable with respect to PSA, clinical stage, preoperative Gleason score, body mass index, smoking status, pathological stage, path Gleason score and margin status. A total of two thromboemoblic events occurred (0.6%) within 30 days of surgery (one in each arm of the study). • Heparin prophylaxis did not influence estimated blood loss (P= 0.076) or haematocrit change from preoperative levels (P= 0.378). Length of stay was comparable between the two groups (1.4 vs 1.3 days; P= 0.159). CONCLUSION: • The incidence of thromboembolism is low after RALP, which may obviate the need for heparin prophylaxis. However, its use is safe and does not impact surgical outcomes. Larger series are needed to confirm the results obtained in the present study.