Avian Ecology and Behaviour

Kidwai Z.   Effect of anthropogenic factors on the abundance of Galliformes in Sariska Tiger Reserve, Rajasthan, India

In press.

Effect of anthropogenic factors against encounter rates of the five species of Galliformes was analyzed in the Sariska Tiger Reserve, Rajasthan, NW India, from February to May 2009. Sixteen transects, ranging from 1.8 to 2 km in length, were laid throughout the 80 km² study area covering all the available habitat types. At each sighting of the target species, 10 m radius circular plots were laid to enumerate degree of various anthropogenic factors making a total of 706 plots throughout the study period. These factors were quantified at each plot in a scale of 0 to 4 (0-none and 4-very high). Multivariate regression was used to estimate the probable relation amongst various anthropogenic factors with the target species on all transects in Software R. The models for each species were selected based on lowest AIC value. It was found that the variables show significant relation with the target species and explain 79%, 67%, 66%, 62%, and 55% of variability in Peafowl, Grey Francolin, Painted Spurfowl, Rain Quail and Jungle Bush Quail, respectively.

Anthropogenic factors; encounter rate; Galliformes; Sariska; transects

Chernetsov N.   Body mass of European Robins Erithacus rubecula at migratory stopovers is strongly habitat-related

In press.

Body mass of European Robins Erithacus rubecula at autumn and spring migratory stopovers on the Courish Spit (Eastern Baltic) was strongly habitat-related, with body mass of birds captured in hardwood significantly higher than body mass of their conspecifics in coastal scrub. At a nearby site, European Robins mist-netted in alder forest were significantly heavier than their conspecifics captured in funnel traps on the edge of young pine plantations just several hundred metres away. Trapping method (standardised ‘passive’ trapping vs. active flushing of birds into the nets) did not consistently bias the mean body mass towards either higher or lower values. Body mass variation between the habitats reached 10%, i.e. it was comparable with Europe-wide variation in the mean body mass in e.g. Eurasian Reed Warbler Acrocephalus scirpaceus or Sedge Warbler A. schoenobaenus known from the literature. Our results caution against making broad regional scale comparisons of mean body mass and condition of songbird migrants at stopover without taking habitat into account. Condition of migrants may vary broadly on the landscape scale and thus distort the geographic patterns.

European robin, body mass, stopover, habitat

Bulyuk V.N.   Age structure of Robins Erithacus rubecula at the eastern Baltic coast during autumn migration and wind conditions

In press.

In many nocturnal migrating passerines the proportion of juvenile individuals at coastal stopover sites during autumn migration is often higher than at inland stopover sites. To investigate this phenomenon called ‘coastal effect’ and test various hypotheses that attempt to explain the low proportion of adult Robins on the Courish Spit on the Baltic Sea, I analysed the data on age structure and body condition of Robins captured in autumns 1994–2003 at Rybachy field station (39176 individuals), and compared wind conditions under which they had migrated. The results showed that the very low proportion of adult Robins at stopovers on the Courish Spit during autumn migration, compared with the proportions of adults at inland stopover sites, cannot be explained by age differences in the timing and routes of migration, or differential behaviour of adult and juvenile birds when selecting stopover sites after an overnight flight. It is assumed that the proportion of adult birds was significantly lower than expected because of the very large number of young individuals that stay on the Courish Spit. The possible reason for the appearance of a large number of young robins was short nocturnal flights after departure from inland.

Robin, Erithacus rubecula, autumn migration, age structure and differences, coastal effect, wind conditions, migratory strategies