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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2006.04.444 Byline: Greg Conway Keywords: STAT3; Transcription factor; Pathfinding; Motoneuron; Zebrafish Abstract: Signal transducers and transcription factors are used in common for developmental cell migration, vasculogenesis, branching morphogenesis, as well as neuronal pathfinding. STAT3, a transcription factor, has been shown to function in all of these processes except neuronal pathfinding. Here, it is shown that STAT3 also facilitates this process. Elimination of STAT3 signaling results in half of zebrafish CaP motoneurons stalling along their ventral pathfinding trajectory. Conversely, constitutive activation leads to precocious branching and redefines CaP axons as a responding population to dorsal guidance cues, resulting in bifurcated axons innervating normal ventral targets as well as additional dorsal muscle groups. These results are consistent with and highlight a fundamental role for STAT3 as a factor promoting cellular responses to guidance cues, not only in nonneural cells but also in pathfinding neurons. Author Affiliation: Life Sciences Division, MS239-11, NASA Ames Research Center, Moffett Field, CA 94035, USA Article History: Received 19 August 2005; Revised 13 April 2006; Accepted 14 April 2006

Summary: Avian electrocutions are a global conservation problem. Power outages associated with electrocutions are problematic for electric utilities focused on delivering reliable electric power. We used contextual data, photographs, line voltage, outage type and assessments of power line components to quantify outage-causing avian electrocutions throughout each of Iran's 31 provinces. We evaluated records of 222 avian-caused outages involving 235 electrocuted birds in 2018. Of these, 14.5% involved species of conservation concern, and a few (at least eight) sparked fires when the plumage of electrocuted birds ignited and fell into dry vegetation. Most avian-caused outages (96%) involved distribution voltages, and 91% involved phase-to-ground contacts attributable to grounded concrete pylons with grounded steel crossarms. These are the most common type of power line structure in Iran. Insulators were involved in 37% of outage-causing avian electrocutions, fused cutouts 29%, transformers 33%, and midspan collisions 1%. Given the numbers of these components in the electrical system, fused cutouts and transformers were involved in more outage-causing avian electrocutions than expected due to chance. The average body size of electrocuted birds was largest for incidents involving suspension insulators, smaller for birds electrocuted on other insulators, and smallest for electrocutions on fused cutouts and transformers. Given that most avian electrocutions do not cause outages and given the similarity across electric systems in the region, our findings likely indicate a much larger avian electrocution concern throughout the middle east. Retrofitting power line components to reduce avian contacts would reduce impacts to wildlife and improve the electrical system's reliability, reduce costs associated with unplanned outages, and reduce risks associated power line ignitions of fires. [ABSTRACT FROM AUTHOR]

It is essential to gain knowledge about the causes and extent of migratory connectivity between stationary periods of migrants to further the understanding of processes affecting populations, and to allow efficient implementation of conservation efforts throughout the annual cycle. Avian migrants likely use optimal routes with respect to mode of locomotion, orientation and migration strategy, influenced by external factors such as wind and topography. In self‐powered flapping flying birds, any increases in fuel loads are associated with added flight costs. Energy‐minimizing migrants are therefore predicted to trade‐off extended detours against reduced travel across ecological barriers with no or limited foraging opportunities.Here, we quantify the extent of detours taken by different populations of European nightjars Caprimulgus europaeus, to test our predictions that they used routes beneficial according to energetic principles and evaluate the effect of route shape on seasonal migratory connectivity.We combined data on birds tracked from breeding sites along a longitudinal gradient from England to Sweden. We analysed the migratory connectivity between breeding and main non‐breeding sites, and en route stopover sites just south of the Sahara desert. We quantified each track's route extension relative to the direct route between breeding and wintering sites, respectively, and contrasted it to the potential detour derived from the barrier reduction along the track while accounting for potential wind effects.Nightjars extended their tracks from the direct route between breeding and main non‐breeding sites as they crossed the Mediterranean Sea–Sahara desert, the major ecological barrier in the Palaearctic–African migration system. These clockwise detours were small for birds from eastern sites but increased from east to west breeding longitude. Routes of the tracked birds were associated with partial reduction in the barrier crossing resulting in a trade‐off between route extension and barrier reduction, as expected in an energy‐minimizing migrant.This study demonstrates how the costs of barrier crossings in prevailing winds can disrupt migratory routes towards slightly different goals, and thereby promote migratory connectivity. This is an important link between individual migration strategies in association with an ecological barrier, and both spatially and demographic population patterns. [ABSTRACT FROM AUTHOR]

In 2014, 12 male Cyprus Wheatears were fitted with geolocators at breeding sites in Cyprus to investigate migration routes and wintering locations. Three males with geolocators (25%) returned in 2015 but we were only able to retrap one and obtain tracking data. Autumn migration by the tracked bird commenced 28 October 2014 and the winter destination was reached five days later on 1 November, involving a total distance of 2200 km with an intermediate stopover site used on two days. The main wintering area was in eastern Sudan, which was occupied until late March with indications of a shift in wintering site during February. Spring migration occurred during March but coincided with the equinox (when geolocator data are unreliable). However, arrival in Cyprus occurred 27 March 2015 and the bird was caught at the same breeding site 17 May 2015. The stopover on autumn migration was in contrast to the results of a previously published study which indicated a single continuous flight (obtained from six tracked individuals). The combined tracking data, from seven individuals, indicate that the winter range may be more extensive and outside the documented main range in Ethiopia. Further tracking of more individuals from more breeding sites in Cyprus, including better representation of age and sex classes, is required to provide a more complete assessment of migration strategies and winter range for this species. [ABSTRACT FROM AUTHOR]

Telemetry has become an important method for studying the biology and ecology of animals. However, the impact of tracking devices and their method of attachment on different species across multiple temporal scales has seldom been assessed. We compared the behavioural and demographic responses of two species of seabird, Lesser Black-backed Gull Larus fuscus and Great Skua Stercorarius skua, to a GPS device attached using a crossover wing harness. We used telemetry information and monitoring of breeding colonies to compare birds equipped with a device and harness, and control birds without an attachment. We assessed whether tagged birds have lower short-term breeding productivity or lower longer term overwinter return rates (indicative of overwinter survival) than controls. For Great Skua, we also assessed whether territory attendance within the breeding season differed between tagged and control birds. As with previous studies on Lesser Black-backed Gull, we found no short-term impacts on breeding productivity or long-term impacts on overwinter return rates. For Great Skua, there was no evidence for impacts of the device and harness on territory attendance or breeding productivity. However, as found by a previous study of Great Skuas using a different (body) harness design, there was strong evidence of reduced overwinter return rates. Consequently, a device attached using a wing harness was considered suitable for long-term deployment on Lesser Black-backed Gulls, but not on Great Skuas. These findings will inform the planning of future tracking studies. [ABSTRACT FROM AUTHOR]

CapsuleThe breeding Woodcock population in Britain in 2013 was estimated at 55 241 males (95% CL: 41 806–69 004), suggesting a large-scale decline that is supported by 2 additional sources of data. AimsTo provide an updated estimate of the size of Britain's breeding Woodcock population, measure recent trends and identify spatial patterns of change. MethodsDisplaying male Woodcock were surveyed at a stratified sample of 834 randomly selected sites. Population estimates were compared with a baseline survey conducted in 2003 and the trend with data from annual Woodcock counts (2003–13) andBird Atlas 2007–11. ResultsWoodcock were estimated to be present at 22% of 1 × 1 km squares containing ≥10 ha of woodland, compared to 35% in 2003. The British population estimate fell by 29% between 2003 and 2013. The Atlas suggests that presence at the 10 × 10 km scale has declined by 56% between 1970 and 2010. Both data sources suggest regional variation in the rate of decline, with losses greatest in the West and South. ConclusionThe Woodcock's population size and breeding range appear to be declining severely across Britain. Regional variation in the rate of decline might be explained by the distribution of large continuous woodlands. [ABSTRACT FROM AUTHOR]

In Europe, the consequences of commercial plantation management for birds of conservation concern are poorly understood. The European Nightjar Caprimulgus europaeus is a species of conservation concern across Europe due to population depletion through habitat loss. Pine plantation-forest is now a key Nightjar nesting habitat, particularly in northwestern Europe, and increased understanding of foraging habitat selection is required. We radiotracked 31 Nightjars in an extensive (185-km2) complex conifer plantation landscape in 2009 and 2010. Home-range 95% kernels for females, paired males and unpaired males were an order of magnitude larger than song territories of paired males, emphasizing the importance of habitats beyond the song territory. Nightjars travelled a mean maximum distance of 747 m from the territory centre each night. Home-range placement relative to landscape composition was examined by compositional analysis. Pre-closure canopy forest (aged 5-10 years) was selected at all scales ( MCP, 95% and 50% kernels), with newly planted forest (aged 0-4 years) also selected within 50% kernels. For telemetry fixes relative to habitat composition within 2 km of their territory centre, individuals again selected pre-closure and newly planted forest, and also grazed grass heath. Open ungrazed habitat was not selected, with implications for open habitat planning for biodiversity conservation within public-owned forests. Despite the Nightjars' selection for younger growth, moth biomass was greater in older forest stands, suggesting that foraging site selection reflects ease of prey capture rather than prey abundance. Within large plantation-forest landscapes, a variety of growth stages is important for this species and our results suggest that grazing of open habitats within and adjacent to forest will additionally benefit the European Nightjar. [ABSTRACT FROM AUTHOR]