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.

Rural landscape dynamics over time and its consequences for habitat preference patterns of the grey partridge Perdix perdix

Intensification of agricultural practices has drastically shaped farmland landscapes and generally caused a decline in spatial and temporal heterogeneity, thus leading to changes in habitat quality and food resources and a decline for most farmland birds Europe-wide. The relationship between complex landscape changes and habitat preferences of animals still remains poorly understood. Particularly, temporal and spatial changes in diversity may affect not only habitat choice but also population sizes. To answer that question, we have looked into a severely declining typical farmland bird species, the grey partridge Perdix perdix in a diverse farmland landscape near Vienna to investigate the specific habitat preferences in respect to the change of agricultural landscape over two decades and geographic scales. Using a dataset collected over 7.64 km² and between 2001 and 2017 around Vienna, we calculated Chesson’s electivity index to study the partridge’s change of habitat selection over time on two scales and between winter and spring in 2017. Although the farmland landscape underwent an ongoing diversification over the two decades, the grey partridges declined in numbers and shifted habitat use to less diverse habitats. During covey period in winter, partridges preferred also human infrastructure reservoirs such as roads and used more diverse areas with smaller fields than during breeding where they selected harvested fields but surprisingly, avoided hedges, fallow land and greening. Known as best partridge habitats, those structures when inappropriately managed might rather function as predator reservoirs. The avoidance behaviour may further be a consequence of increasing landscape structuring and edge effects by civilisation constructions. Besides, the loss in size and quality of partridge farmland is altered by crop choice and pesticides reducing plant and insect food. With declining breeding pairs, the grey partridge does not seem to adjust to these unsustainable landscape changes and farmland practices.

Coexistence without conflict, the recovery of Ireland’s endangered wild grey partridge Perdix perdix

By 1995, Ireland’s wild grey partridge (Perdix perdix) was extinct nationally as a breeding species on farmland. The two populations remaining were confined to Ireland’s industrial cutaway peat bogs. One of these populations was deemed viable. In 1996, the National Parks and Wildlife Service of Ireland and the Irish Grey Partridge Conservation Trust established a conservation project to prevent the extirpation of this population. In this paper, we explore the impact of each management factor on two key demographic response variables: chick survival rates and the number of breeding pairs. The numbers of linear metres of nesting strips had the most significantly positive effect on spring pairs, followed by the total number of supplementary food hoppers and the total hectares of brood-rearing and over-winter cover. Counterintuitively, encounters with Hen Harriers (Circus cyaneus) did not negatively affect chick survival or the number of spring pairs. While we cannot rule out the contribution of each explanatory variable, none had a statistically significant effect on chick survival, suggesting there may be locally confounding factors that our model could not capture. The weather conditions during the peak hatching period had a significant influence on chick survival, with the average maximum temperature observed in June having the strongest positive association with an increase of 1 °C in the average maximum temperature in June associated with an increase in chick survival of 9.4% on average. Conversely, for every additional 1 mm of rain in June, there was a 0.23% drop in chick survival on average.

BLOOD PLASMA BIOCHEMICAL PARAMETERS OF CAPTIVE BLACK-NECKED PHEASANT (PHASIANUS COLCHICUS), GRAY PARTRIDGE (PERDIX PERDIX) AND CHUKAR PARTRIDGE (ALECTORIS CHUKAR) OF BOTH SEXES IN BULGARIA

In the study, 36 (n=12 by species, n=6 by sex) blood samples were taken from a captive, adult, clinically healthy, Black-necked pheasants or Southern Caucasus pheasants (Phasianus col. colchicus), Gray partridge (Perdix perdix), and Chukar partridge (Alectoris chukar) for plasma biochemical analyses. The investigated plasma biochemical parameters were Creatinine, Uric acid, Aspartate aminotransferase (AST), and Alanine aminotransferase (ALT). Significant differences (P<0.05) among both sexes were found in the activity of ALT in Black-necked pheasants. Creatinine levels are relatively close in value between the sexes in all three species, slightly higher in males. Uric acid values in male birds are much higher than in female game birds in all three species. AST and ALT activities in male pheasants were higher when compared to the females, while the trend was reversed in sex at Gray partridges.

Research Into Practice: Gray Partridge (Perdix perdix) Restoration in Southern England

The gray partridge Perdix perdix was once a common breeding bird in Britain and a traditional quarry species. Its numbers have declined by over 90% over the last 50 years, and there have been similar declines across Europe. Since 1968 the Game and Wildlife Conservation Trust (GWCT) has undertaken research on this decline and identified three main reasons for it in Britain: disappearance of nesting habitat, reduction in area of brood-rearing habitat and increased pressure from predators. A nature-sparing mindset is not compatible with the conservation of a once-widespread species of farmed land such as the gray partridge, which requires a nature-sharing viewpoint. A gray partridge recovery program had to be tailored toward farmers and their advisors, requiring scientifically proven, costed, pragmatic and simple solutions. The difficulty is in convincing farmers and land managers to take up the challenge, adopt the conservation package and reverse the decline of this species. An important means of addressing this is providing demonstration sites where farmers can go to see how appropriate and practical management leads to successful restoration of gray partridge numbers. We provide two detailed examples of demonstrations in the United Kingdom, concentrating on gray partridge abundance and demography, but also considering the consequences for wider farmland biodiversity. At both demonstration sites the abundance of gray partridges was restored to abundances approaching those of 50 years ago (an average, over 10 years, of 11.3 spring pairs/km2 on one site and 13.2 pairs/km2 on the other). Obstacles to a more widespread adoption of the package among United Kingdom farmers are discussed as are signposts on how these are being addressed, both in United Kingdom and in Europe.