Evaluating landscape connectivity in fragmented habitats: Cantabrian capercaillie (Tetrao urogallus cantabricus) in northern Spain

El estudio de los factores ambientales que pueden explicar los niveles de estrés fisiológico en poblaciones naturales es de vital importancia para especies vulnerables, ya que puede influir en la mortalidad de los individuos y, por tanto, en la viabilidad poblacional. En este trabajo se exploran los condicionantes ambientales que pueden explicar las variaciones de estrés fisiológico medido a través de niveles de corticosterona en plumas de urogallo cantábrico (Tetrao urogallus cantabricus). Se emplearon muestras recogidas de individuos en cautividad y de individuos silvestres. Las muestras recogidas de los individuos silvestres se recopilaron desde 1998 hasta 2017 y se consideraron 35 variables climáticas de temperatura y precipitación. Los análisis de repetibilidad sugirieron que los niveles de corticosterona en la combinación de plumas corporales y secundarias fueron repetibles dentro de individuos, mientras que en la combinación de plumas corporales y primarias no lo fueron, por lo que se consideraron sólo las medidas de las plumas corporales y secundarias. Los resultados indicaron que los individuos en cautividad tuvieron un menor estrés fisiológico y que, en individuos silvestres, hubo un incremento de los niveles de estrés hasta estabilizarse en los últimos años de estudio. Ninguna variable climática estuvo relacionada con los niveles de estrés fisiológico. Especulamos que la tendencia temporal en los niveles de estrés podría estar reflejando limitaciones alimenticias, quizá asociadas a cambios en la estructura o composición del hábitat o interacciones con otras especies silvestres o ganado doméstico, lo que podría explicar el menor estrés fisiológico de los individuos en cautividad. Desde el punto de vista metodológico, las plumas secundarias o corporales, independientemente del sexo, serían las preferibles para establecer un monitoreo del estrés fisiológico del urogallo en condiciones naturales o de cautividad.

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Prioritizing highway defragmentation locations for restoring landscape connectivity

Environmental Conservation ◽

10.1017/s0376892913000325 ◽

2013 ◽

Vol 41 (2) ◽

pp. 157-164 ◽

Cited By ~ 20

Author(s):

MIKEL GURRUTXAGA ◽

SANTIAGO SAURA

Keyword(s):

Landscape Connectivity ◽

Basque Country ◽

High Volume ◽

Illustrative Case ◽

Area Network ◽

Northern Spain ◽

Relative Contribution ◽

Crossing Structures ◽

Wildlife Crossing Structures ◽

Illustrative Case Study

SUMMARYTransport infrastructures are a major driver of global landscape change. In many areas, highways were built before environmental impact assessments required the implementation of wildlife crossing structures. A fundamental task in the development of ecological networks is identifying areas where dispersal pathways of vulnerable populations may be blocked or affected by high volume roads. Financial considerations may limit investment, thus it is vital to establish the relative contribution of each road defragmentation location to upholding habitat connectivity and availability. In this paper, recent methodological developments in habitat network analysis, derived from the probability of connectivity index, were refined and used to evaluate the role of each highway defragmentation location in restoring landscape connectivity. The forest protected area network in the Basque country (northern Spain) was selected as an illustrative case study. The proposed approach was able to quantify and effectively account for a combination of factors determining the contribution of each highway defragmentation location to upholding connectivity, which are rarely jointly considered in analyses oriented to support restoration decisions in landscapes affected by the barrier effect of transport infrastructures. The contribution to connectivity of each defragmentation location depended on its topological position in the landscape, on the relative decrease in the effective distance among habitat areas that results from the permeability restoration at that location, on the distance from the defragmentation location to other alternative wildlife crossing structures already existing in the landscape, on the amount of habitat in the areas connected by the linkages that run through the defragmentation location and on the dispersal abilities of the focal species.

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Trends in the abundance of Cantabrian Capercaillie Tetrao urogallus cantabricus at leks on the southern slope of the Cantabrian Mountains, north-west Spain

Bird Conservation International ◽

10.1017/s0959270905000626 ◽

2005 ◽

Vol 15 (4) ◽

pp. 397-409 ◽

Cited By ~ 8

Author(s):

CÉSAR J. POLLO ◽

LUIS ROBLES ◽

JUAN M. SEIJAS ◽

ÁNGEL GARCÍA-MIRANDA ◽

RAFAEL OTERO

Keyword(s):

Population Decline ◽

Small Population ◽

Limiting Factors ◽

Tetrao Urogallus ◽

Southern Slope ◽

Cantabrian Mountains ◽

North West ◽

Area Of Occupancy ◽

Tetrao Urogallus Cantabricus ◽

Number Of Males

We analysed the trend of the number of singing males of Cantabrian Capercaillie Tetrao urogallus cantabricus in 207 leks on the southern slope of the Cantabrian mountains, north-west Spain, in the period 1981 to 2003. The area of occupancy in 1981–1982 covered up to approximately 2,070 km2, but in 2000–2003 it was 693 km2, a 66% area reduction in 22 years. The 1981–1982 census estimated a minimum number of 274 singing male Capercaillie on the southern slope, but in 2000–2003 only an estimated 81 males were recorded, a reduction of 70%. A linear regression was used to detect and describe the changes in the size of the total population of the southern slope as well as individual subpopulations. The overall trend for the total subpopulations was a significant decrease in the number of males (y = 39.94−0.018x; R2 = 0.944, P < 0.001). The negative regression slopes indicated that the number of males had fallen in all the subpopulations considered. In the western core area the greatest annual mean rate of decline was detected in the Sierra de Picos de Ancares subpopulation (−6.22%) and in the eastern core in the Sierra de Riaño subpopulation (−3.43%). The principal local limiting factors (habitat fragmentation, human disturbance, small population size and competition) that have caused the population decline are discussed, together with the demographic, genetic and evolutionary consequences for the surviving subpopulations.

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Integrating landscape connectivity in broad-scale forest planning through a new graph-based habitat availability methodology: application to capercaillie (Tetrao urogallus) in Catalonia (NE Spain)

European Journal of Forest Research ◽

10.1007/s10342-006-0165-z ◽

2007 ◽

Vol 127 (1) ◽

pp. 23-31 ◽

Cited By ~ 65

Author(s):

Lucía Pascual-Hortal ◽

Santiago Saura

Keyword(s):

Landscape Connectivity ◽

Forest Planning ◽

Habitat Availability ◽

Tetrao Urogallus ◽

Broad Scale ◽

Ne Spain

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Severe decline in Cantabrian Capercaillie Tetrao urogallus cantabricus habitat use after construction of a wind farm

Bird Conservation International ◽

10.1017/s0959270914000471 ◽

2015 ◽

Vol 26 (2) ◽

pp. 256-261 ◽

Cited By ~ 3

Author(s):

MANUEL A. GONZÁLEZ ◽

SERGIO GARCÍA-TEJERO ◽

ERIC WENGERT ◽

BENITO FUERTES

Keyword(s):

Habitat Use ◽

Wind Farm ◽

Tetrao Urogallus ◽

Mediterranean Forests ◽

Cantabrian Mountains ◽

Conservation Areas ◽

North West ◽

Negative Effect ◽

Tetrao Urogallus Cantabricus ◽

One Year

SummaryTetrao urogallus cantabricus is the most endangered capercaillie subspecies and unlike the others it inhabits deciduous forests in the Cantabrian Mountains (north-west Spain). Its southernmost distribution occurs in Mediterranean forests outside conservation areas where wind farm construction is increasing. We surveyed Cantabrian Capercaillie presence in a wintering site one year before and four years after wind farm construction. Sign abundance greatly decreased after wind farm construction indicating a likely negative effect on Cantabrian Capercaillie habitat use. According to the precautionary principle, in order to conserve Cantabrian Capercaillie, all its range should be legally protected to avoid further wind farm construction and human disturbance.

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