New data on the status and ecology of a galliform at risk of extinction: the Pyrenean grey partridge (Perdix perdix hispaniensis) in the Iberian System (Soria, Spain)

A study was conducted in 2008–2010 to gain knowledge on the status and ecology of the endangered subspecies of grey partridge (Perdix perdix hispaniensis), at its southernmost range edge. From an historic breeding range of 28,300 ha, 15 different coveys (adults with juveniles) were observed in an area comprising 5,550 ha, with an estimated minimum autumn population size of 103–113 birds and a maximum of 163–181 birds. Spring pair density was estimated at 2.3 pairs/1,000 ha, and when considering only coveys, 6.8 partridges/1,000 ha. The majority of birds were located at an altitude above 1,690 m a.s.l., mainly in mountain shrubland (especially Calluna vulgaris and Erica spp.). Habitat loss was the most important threat for the species’ conservation. In conclusion, efforts should prioritize urgent habitat recovery and monitoring in order to change the fate of the species.

New data on the status and ecology of a galliform at risk of extinction: the Pyrenean grey partridge (Perdix perdix hispaniensis) in the Iberian System (Soria, Spain)

A study was conducted in 2008–2010 to gain knowledge on the status and ecology of the endangered subspecies of grey partridge (Perdix perdix hispaniensis), at its southernmost range edge. From an historic breeding range of 28,300 ha, 15 different coveys (adults with juveniles) were observed in an area comprising 5,550 ha, with an estimated minimum autumn population size of 103–113 birds and a maximum of 163–181 birds. Spring pair density was estimated at 2.3 pairs/1,000 ha, and when considering only coveys, 6.8 partridges/1,000 ha. The majority of birds were located at an altitude above 1,690 m a.s.l., mainly in mountain shrubland (especially Calluna vulgaris and Erica spp.). Habitat loss was the most important threat for the species’ conservation. In conclusion, efforts should prioritize urgent habitat recovery and monitoring in order to change the fate of the species.

Recovery of A Native Tree Following Removal of An Invasive Competitor In The Context of Potential Endangered Bird Habitat

Invasive species removal is a common focus in restoration ecology, but the ultimate goal of native plant species recovery and habitat recovery is often elusive. Control of invasive Tamarix spp. shrubs in the American Southwest has only sometimes led to increased native species cover; this is of particular concern for the protection of the endangered Southwestern willow flycatcher (Empidonax extimus trailii, abbr. SWFL) that nests readily in Tamarix when native Salix canopy is absent. If we can identify the conditions that lead to more native trees as well as habitat protection for the SWFL, we can prioritize restoration efforts more effectively and reduce conflict between conservation goals. To determine whether reduction in the invasive Tamarix led to more Salix cover (and thus no net loss in SWFL habitat), we compiled data on vegetation, soils, and geographic conditions in 260 sites where Tamarix had been subject to control efforts and 132 positive and negative reference sites. We found that (1) reduction in Tamarix only increased Salix cover in wetter sites, and was greater when a particular, low-disturbance removal method was used; however the increase did not typically compensate for the overall losses in canopy cover, and (2) Salix cover was generally highest in locations with low drought stress, as reflected by soil properties, distance to water, and climate. These results suggest that the presence and recovery of Salix is dependent on its relatively narrow environmental niche, in contrast with Tamarix’s broader one. Thus, although abundance of Salix and Tamarix was negatively correlated, this is likely because of Salix’s different niche, as much as or more than direct interspecific competition. Our findings demonstrate that removal of an invasive species does not necessarily lead to reestablishment of the native species they appeared to displace. We suggest that in the case of promoting habitat for SWFL and other birds, outcomes of restoration activity can be improved by focusing Tamarix removal efforts on sites more likely to promote Salix growth based on environmental characteristics.

Lag in Hydrologic Recovery Following Extreme Meteorological Drought Events: Implications for Ecological Water Requirements

Hydrological regimes, being strongly impacted by climate change, play a vital role in maintaining the integrity of aquatic river habitats. We investigated lag in hydrologic recovery following extreme meteorological drought events, and we also discussed its implications in the assessment of ecological environment flow. We used monthly anomalies of three specific hydrometeorological variables (precipitation, streamflow, and baseflow) to identify drought, while we used the Chapman–Maxwell method (the CM filter) with recession constant calculated from Automatic Baseflow Identification Technique (ABIT) to separate baseflow. Results showed that: (i) Compared to the default recession parameter (α = 0.925), the CM filter with the ABIT estimate (α = 0.984) separated baseflow more accurately. (ii) Hydrological drought, resulting from meteorological drought, reflected the duration and intensity of meteorological drought; namely, longer meteorological drought periods resulted in longer hydrological drought periods. Interestingly, the time lag in streamflow and baseflow indicated that aquatic ecosystem habitat recovery also lagged behind meteorological drought. (iii) Assessing environmental flow by quantifying drought provided greater detail on hydrological regimes compared to abrupt changes, such as the increased hydrological periods and the different environment flows obtained. Taken together, our results indicated that the hydrological response in streamflow and baseflow (e.g., the time lag and the precipitation recovery rate (Pr)) played a vital role in the assessment of environmental flow.

Muntjac and Water Deer

Muntjac and water deer were introduced to Britain from East Asia. This book provides a comprehensive overview of their natural history and the management of their environmental impacts. In lowland England, muntjac deer are one of the drivers of changes in woodland structure and species composition, and many of the principles relating to such woodland impact are also applicable to the activities of other species of deer. Interest in environmental impacts of deer is not solely restricted to woodlands. The highest densities of water deer occur in wetlands, where there is potential for conflict, and considerable numbers are also found on agricultural land. Muntjac have also settled in suburbia and frequently cause impacts there. Conservationists and national decision makers are concerned both about invasive alien species and about increasing deer populations. The first section covers the natural history of both species including: breeding biology, deer in the field, colonisation of Britain, a detailed look at colonisation in a single county, methods for studying deer populations and a review of deer population numbers. The second section covers environmental impact: risk assessment, impact management, control of muntjac, effect of muntjac browsing and grazing, habitat recovery from muntjac impacts and a study on the impacts of water deer. The section concludes with an overview of management and monitoring. The costs and benefits of both species are discussed, and questions asked about whether we are getting on top of problems caused by muntjac (locally and nationally) and will water deer turn out to be similar to muntjac? Attitudes and approaches to these species are changing: with water deer we are actively studying whether it might be an environmental problem, not waiting until after it has obviously become one. What will happen to distribution, numbers, impacts and attitudes in the future? Will water deer ever become a suburban animal? What does the future hold for water deer in China and Korea - and how important is the English population as a global conservation resource?