Dataset Information

Predation of young tortoises by ravens: the effect of habitat structure on tortoise detectability and abundance.

ABSTRACT: The predation of young tortoise is considered a major cause of mortality for many tortoise species. The predation by common ravens has been identified as being responsible for significant decreases in tortoise populations. Mediterranean spur-thighed tortoise hatchlings and juveniles in Maamora forest (Morocco) were studied in order to describe the size/age class predation of common ravens on young tortoises and infer the drivers of predation risk and population abundance. The results showed a high level of predation on young tortoises (<75?mm carapace length) attributed to ravens in areas with low vegetation cover, representing 100% of the cases of mortality (n?=?147), but it was moderate in covered areas (n?=?19), representing 12-27%. The population structure of living juveniles differed significantly between covered and uncovered areas, thus suggesting that raven predation might modify juvenile population structure. Finally, N-mixture models showed a positive relationship between (i) bare cover and tortoise detectability that is only evidenced when the plot is far from a perch and (ii) population abundance and shrub species-richness, being higher in uncovered areas. Our results improve the knowledge on predation and survival on this critical stage in life, which is crucial for the conservation of the Mediterranean spur-thighed tortoise.

SUBMITTER: Segura A

PROVIDER: S-EPMC7002411 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Predation of young tortoises by ravens: the effect of habitat structure on tortoise detectability and abundance.

Segura Amalia A Jimenez José J Acevedo Pelayo P

Scientific reports 20200205 1

The predation of young tortoise is considered a major cause of mortality for many tortoise species. The predation by common ravens has been identified as being responsible for significant decreases in tortoise populations. Mediterranean spur-thighed tortoise hatchlings and juveniles in Maamora forest (Morocco) were studied in order to describe the size/age class predation of common ravens on young tortoises and infer the drivers of predation risk and population abundance. The results showed a hi ...[more]

PMID: 32024887

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Dataset Information

Predation of young tortoises by ravens: the effect of habitat structure on tortoise detectability and abundance.

Publications

Predation of young tortoises by ravens: the effect of habitat structure on tortoise detectability and abundance.

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