Northern Shrike (Lanius excubitor) Science Article 6 abstract The great grey shrike, Lanius excubitor, is known to be a raptor-like passerine. In addition to invertebrate prey, its diet also consists of vertebrates, including small birds. We examined the effect of presence of the great grey shrike on the breeding assemblages of small passerine birds in […]
Category: North America
Repeatability of Measurements and Shrinkage after Skinning: the Case of the Great Grey Shrike Lanius excubitor
Northern Shrike (Lanius excubitor) Science Article 8 abstract In studies on avian systematics and ecology, data from birds in museum collections are often used. Therefore, it is very important to test how representative such material is. However, museum specimens are usually handled, preserved and kept in different ways, which complicates the comparative use of measurements […]
Animals of different phenotype differentially utilise dietary niche-the case of the Great Grey Shrike Lanius excubitor
Northern Shrike (Lanius excubitor) Science Article 9 abstract We tested the morphological trait utility in Great Grey Shrike Lanius excubitor. The food composition was used as an indicator of phenotype performance advantage in utilising of particular dietary niche. Mounts and accompanying data (measurements and stomach contents) from the Slovak extensive collection, involving adult birds obtained […]
Interspecific feeding of a Great Grey Shrike (Lanius excubitor) fledgling by adult Yellowhammers (Emberiza citrinella)
Northern Shrike (Lanius excubitor) Science Article 4 abstract On 25 May 2003, near the village Budy (Biebrza Marshes, East Poland), interspecific feedingof a Great Grey Shrike (Lanius excubitor) fledgling by adult Yellowhammers (Emberiza citrinella) wasobserved. R. Drozdz, M. Hromada and P. Tryjanowski, BIOLOGICAL LETT. 2004, 41(2): 185n187 Download article download full text (pdf)
Flocks of the Great Grey Shrike (Lanius excubitor) on migration
Northern Shrike (Lanius excubitor) Science Article 5 abstract Great Grey Shrikes are usually territorial all the year round. However, flocks of up to 15 individuals have been observed on migration in Poland recently. On 3rd November 2001 in the morning, I observed a flock of 110 Great Grey Shrikes near ponds in Zimno (E Poland). […]
The Little Blue Heron in California
Little Blue Heron (Egretta caerulea) Science Article 4 abstract On 4 July 1976 William T. Everett, Curtis Stuteville and I discovered an adult Little Blue Heron (Egretta caerulea) near the mouth of the New River at the south end of the Salton Sea, Imperial County. This bird was perching in an area of drowned trees […]
Aplomado Falcon Steals Prey From Little Blue Heron
Little Blue Heron (Egretta caerulea) Science Article 2 abstract A juvenile male Aplomado Falcon (Falcofemoralis) was observed to steal crayfish(Cambarus diogenes) from Little Blue Herons (Egretta caerulea). Crayfish are not known tobe a common prey item of the Aplomado Falcon. To our knowledge this is the first instanceof piracy reported for this falcon. Falcons of […]
Predation as a selective force on foraging herons: effects of plumage color and flocking
Little Blue Heron (Egretta caerulea) Science Article 6 abstract Experiments using model herons in natural mangrove habitats demonstrated that more hawks are attracted to white than to blue herons. Both Common Black-Hawks (Buteogalluas nthracinus) and crocodiles (Crocodylus acutus) were observed preying on adult herons in Panama. Solitary herons were at greater risk than flocked foragers. […]
Notes on the plumages and generic status of the Little Blue Heron
Little Blue Heron (Egretta caerulea) Science Article 3 abstract The juvenal plumage of the Little Blue Heron (Florida caerulea) has always been described as white with dull brownish gray tips to the primaries (Palmer, 1962: 428, and earlier authors). In September 1962, when Dickermanw as collectingb lood specimensfr om nestling h rons in a large […]
Influence of plumage colour on prey response:does habitat alter heron crypsis to prey?
Little Blue Heron (Egretta caerulea) Science Article 5 abstract The foraging strategies of wading birds may be influenced by their degree of crypsis to aquatic prey. Whiteplumage has been hypothesized to be adaptive for herons hunting in open water habitats. We tested thishypothesis with laboratory and field experiments with multiple prey species.We investigated the responseof […]