A Note on Bernstein′s Theorems

Lithner, Johan; Wójcik, Adam P.

doi:10.1006/jath.1995.1053

Cited by 1 publication

(2 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Under övriga år iakttogs inte någon ollonproduktion (Figur 2). (Kjellén & Lindström 1993, Lithner 1995 Vi fann ett signifikant samband mellan stora antal bokollon och registrerade pärlugglor följande år. För horn-och kattuggla fann vi inte något sådant samband inom vårt huvudområde.…”

Section: Resultatunclassified

“…In the remaining winters, from 1991/92 through 1999/2000, no flock as large as 100 Bramblings were observed in Blekinge, not even during the winter of 1992/93 despite the very good year for beechnut production in 1992. In January and February 1993, a very large flock containing roughly two million birds was observed in the northwestern part of the province of Scania (Kjellén & Lindström 1993, Lithner 1995.…”

Section: Brambling Abundancementioning

confidence: 99%

See 1 more Smart Citation

Abundance of owls and Bramblings Fringilla montifringilla in relation to mast seeding in south-eastern Sweden

Lithner¹,

Jonsson

2002

Ornis Svec

View full text Add to dashboard Cite

We investigated the relationship between mast seeding in beech Fagus sylvaticus and oak Quercus spp., and the occurrence of the rodent-dependent predators Tengmalm’s Owl Aegolius funereus, Long-eared Owl Asio otus and Tawny Owl Strix aluco in south-eastern Sweden (Blekinge) 1992—2000. We also compared available data on seed production with data on winter flocks of Brambling Fringilla montifringilla, mainly depending on beech seeds as winter food. Years of good beech mast production were followed by years of high frequency of Tengmalm’s Owl and Long-eared Owl, indicating a rapid numerical response to improved food conditions. The Tawny Owl did not respond in the same way, but tended to reach high densities two years after mast seeding. These results suggest that mast seed production may influence the populations of rodent-feeding predators, and that the numerical response may be very rapid in potentially nomadic specialist predators. This was indicated particularly for the Tengmalm´s Owls arriving in Blekinge rather late in spring of 1999. Winters following good beech mast production normally held large numbers of Bramblings. However Bramblings were absent in Blekinge during the winter of 1992/93 despite the very good year for beechnut production in 1992. Thus, low number of Bramblings was no reliable indication for low numbers of owls the following spring.

show abstract

Section: Resultatunclassified

Section: Brambling Abundancementioning

confidence: 99%