The breeding success of Lesser Spotted Woodpeckers Dendrocopos minor is now lower in England than found in studies elsewhere in Europe. Nests were monitored in three regions of England, recording survival and causes of failure. We measured aspects of food limitation and parental care, rainfall and Great Spotted Woodpecker interactions at nests, to explore whether there was any evidence that these factors were related to breeding success. We compared results to other studies from the UK and continental Europe. Nest survival was 52%. The average number of chicks produced from successful nests was 2.8. Chick-stage daily nest survival was positively related to provisioning rates, indicating that food supply may be limiting. The most common cause of nest failure was presumed starvation of chicks after the disappearance of an adult. Some females ceased visiting nests, leaving provisioning solely to the male. This behaviour has been reported elsewhere in Europe, but in the present study males were unable to compensate fully by increasing their provisioning rates, leading to poor nest survival. Provisioning rates and chick-stage daily nest survival were negatively associated with rainfall. Nest predation by Great Spotted Woodpeckers occurred but was a less frequent cause of failure. Aggressive interactions were recorded between the two woodpecker species but these were unrelated to breeding parameters. Low breeding success is most probably related to food shortages in the breeding period. Simple population modelling using parameters from the present study and from published work shows that if the low productivity that we have observed is replicated throughout Britain, it would be sufficient to account for the observed population decline.
Source:
Elisabeth C. Charman, Ken W. Smith, Ian A. Dillon, Steve Dodd, Derek J. Gruar, Andrew Cristinacce, Phil V. Grice, Richard D. Gregory (2012) Drivers of low breeding success in the Lesser Spotted Woodpecker Dendrocopos minor in England: testing hypotheses for the decline. Bird Study DOI:10.1080/00063657.2012.662941
http://www.tandfonline.com/doi/abs/10.1080/00063657.2012.662941
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