Importance of climatic and environmental change in the demography of a multi-brooded passerine, the woodlark Lullula arborea
Article first published online: 6 JUL 2009
© 2009 The Authors. Journal compilation © 2009 British Ecological Society
Journal of Animal Ecology
Volume 78, Issue 6, pages 1191–1202, November 2009
How to Cite
Wright, L. J., Hoblyn, R. A., Green, R. E., Bowden, C. G. R., Mallord, J. W., Sutherland, W. J. and Dolman, P. M. (2009), Importance of climatic and environmental change in the demography of a multi-brooded passerine, the woodlark Lullula arborea. Journal of Animal Ecology, 78: 1191–1202. doi: 10.1111/j.1365-2656.2009.01582.x
- Issue published online: 13 OCT 2009
- Article first published online: 6 JUL 2009
- Received 13 August 2007; accepted 28 May 2009 Handling Editor: Jean Clobert
- climate change;
- nest predation;
- population dynamics
1. We examined the influence of local weather conditions on reproductive success, timing of breeding and survival in a population of a multi-brooded ground nesting passerine (woodlark Lullula arborea) over 35 years.
2. Woodlarks laid larger clutches when rainfall was low and temperature high during the egg-laying and pre-laying period. Nest success increased with higher temperatures during the nesting period. In successful nests, the number of chicks fledged per egg laid was greater when weather was drier during the brood stage.
3. Although woodlarks bred earlier in years with warmer early spring temperatures, with the onset of breeding varying by 25 days, there was no significant advance in the onset of breeding over the 35 years of study, due to considerable inter-annual variability, and no overall trend, in weather.
4. Simulation modelling of annual reproductive output demonstrated that earlier breeding could increase productivity by 23·5% in the warmest compared to the coldest year, due to birds having more nesting attempts. Other effects of weather on productivity affected breeding output to a lesser extent.
5. Effects of weather on productivity were minor compared to an increased rate of nest predation through the period of study, which reduced productivity by 49·8% by 2004 compared to 1971.
6. Turning points analysis identified three distinct demographic periods: from1971 to 1988 the population grew slowly, during 1988–1999 the population grew rapidly, but after 1999 the population declined. Increased population growth after 1988 was associated with higher first-year survival rates (estimated using a population model). Population decline after 1999 was caused by a combination of reduced productivity (resulting from increased nest failure rates attributed to predation) and lower first-year survival rates, that appear unrelated to winter temperature.
7. Climate change (long-term changes in weather) did not explain the marked changes observed in the population trajectory over 35 years. We suggest that understanding effects of both climate and habitat change on populations is essential in predictive population modelling.