A test of the dear enemy phenomenon in the Eurasian beaver

Rosell, Frank; Bjørkøyli, Tore

doi:10.1006/anbe.2002.3010

Cited by 66 publications

(78 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The extraction of castoreum was performed by making a lateral incision through the outer layer of the castor sacs, thereby revealing the castoreum, which in turn could be removed from the pocket lumen. Anal gland secretion (AGS), which has a more liquid consistency, was squeezed out by applying external pressure on the anal pocket (Rosell and Bjørkøyli 2002). All samples were stored in glass vials and frozen until use.…”

Section: Scent Donors and Collection Of Scent Samplesmentioning

confidence: 99%

“…The distance between the two pairs varied between trials but was never less than 10 m. We placed the ESMs of each pair 30 cm apart and within 50 cm of the water's edge (for details see Fig. 1 in Rosell and Bjørkøyli 2002). The ESMs were constructed where the beavers could easily make a land visit (walk onto land).…”

Section: Experimental Designmentioning

confidence: 99%

“…They are strictly territorial and rely on scent to deter potential intruders (Rosell 2002;Rosell and Bjørkøyli 2002).…”

Section: Introductionmentioning

confidence: 99%

“…Scent is used for intraspecific purposes such as individual, kin, family-nonfamily, and mate recognition (Sun and Müller-Schwarze 1999;Rosell 2002;Rosell and Bjørkøyli 2002). It is probably also used in species discrimination (Ø.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Subspecies discrimination in the Scandinavian beaver (Castor fiber): combining behavioral and chemical evidence

Rosell¹,

Steifetten²

2004

Can. J. Zool.

Self Cite

View full text Add to dashboard Cite

Geographic isolation is one of several models that has been proposed to explain the evolutionary course of speciation. In this study, we examined how geographical isolation may affect subspecies discrimination in the freeranging Scandinavian beaver (Castor fiber fiber L., 1758) by simulating a territorial intrusion by using scent (castoreum and anal gland secretion) from a con-subspecific (N = 8 for castoreum and N = 7 for anal gland secretion) and a hetero-subspecific (Castor fiber albicus Matschie, 1907; N = 2 for both castoreum and anal gland secretion). Direct observations of 33 families during evenings showed that beavers (i) sniffed castoreum but not anal gland secretion from C. f. fiber significantly longer than from C. f. albicus and (ii) responded aggressively (i.e., stood on the mound on their hind feet, pawing and (or) overmarking) significantly longer to castoreum but not anal gland secretion from C. f. fiber than from C. f. albicus. When experimental scent mounds were allowed to remain overnight, the response was significantly stronger to castoreum but not to anal gland secretion from C. f. fiber than from C. f. albicus. Gas chromatographic comparisons of castoreum and anal gland secretion from the two subspecies supported our behavioral observations for castoreum but not for anal gland secretion. These findings suggest that geographical isolation has developed discriminatory abilities in C. f. fiber. We further suggest that the proximate factors involved are of environmental origin.Résumé : L'isolement géographique est l'un de plusieurs modèles proposés pour expliquer le développement de la spé-ciation au cours de l'évolution. Notre étude examine comment l'isolement géographique peut affecter la reconnaissance des sous-espèces chez le castor de Scandinavie (Castor fiber fiber L., 1758) sauvage par la simulation d'une intrusion territoriale au moyen d'odeurs (castoréum et sécrétions de la glande anale) provenant d'animaux la même sous-espèce (castoréum, N = 8, sécrétions de la glande anale, N = 7) et d'une autre sous-espèce (Castor fiber albicus Matschie, 1907; N = 2 pour le castoréum et les sécrétions de la glande anale). Des observations directes de 33 familles en soirée indiquent que les castors (i) reniflent le castoréum, mais pas les sécrétions des glandes anales, de C. f. fiber significativement plus longtemps que les mêmes substances provenant de C. f. albicus et (ii) qu'ils réagissent agressivement (position debout sur les pattes arrières sur les monticules, coups de pattes et (ou) marquage excessif) significativement plus longtemps au castoréum, mais non aux sécrétions des glandes anales, de C. f. fiber, qu'aux mêmes substances provenant de C. f. albicus. Si les monticules portant les odeurs sont laissés toute la nuit, la réaction est significativement plus forte au castoréum, mais non aux sécrétions de la glande anale, de C. f. fiber qu'aux mêmes substances provenant de C. f. albicus. Des analyses comparatives par chromatographie en phase gazeuse du castoréum et des sécrétions d...

show abstract

Section: Scent Donors and Collection Of Scent Samplesmentioning

confidence: 99%

Section: Experimental Designmentioning

confidence: 99%

“…They are strictly territorial and rely on scent to deter potential intruders (Rosell 2002;Rosell and Bjørkøyli 2002).…”

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Subspecies discrimination in the Scandinavian beaver (Castor fiber): combining behavioral and chemical evidence

Rosell¹,

Steifetten²

2004

Can. J. Zool.

Self Cite

View full text Add to dashboard Cite

show abstract

“…In these individuals, the capacity to differentiate the acoustic signals emitted by conspecifics has major implications for the recognition and discrimination of foreigners and neighbours, a phenomenon called "neighbour-stranger discrimination" (NSD). The phenomenon was described in birds species (Stoddard, 1996) as well as other taxonomic groups such as insects (Gordon 1989, Thomas et al, 1999, amphibians (Bee and Gerhardt, 2001), fish (McGregor and Westby, 1992), reptiles (Whiting, 1999), and mammals (Rosell and Bjørkøyli, 2002).…”

Section: Introductionmentioning

confidence: 99%

Neighbours vs. strangers discrimination in Water Rail (Rallus aquaticus)

Stermin¹,

David²,

Drăgoi³

et al. 2017

Studia UBB Biologia

View full text Add to dashboard Cite

SUMMARY.Water Rail (Rallus aquaticus) manifest strongly intra-and interspecific aggressivity. In our study we test the Water Rail's reaction to the calls of conspecifics neighbours and strangers, to conclude if they express the "neighbour-stranger discrimination" (NSD) and / or "the dear enemy effect" (DEE) behaviour as evolutionary attributes that would reduce the energy consumption. Ten points located 100 m apart inside the Sic Reedbeds wetland were selected. In each point the acoustic reactions to spontaneous and playback of territorial Water Rail's call were counted for three days (18, 19 and 20 April 2011), between 6:00 -8:00 p.m.. A statistically significant difference was found between the number of songs recorded after spontaneous activity and the number of calls recorded after playback. The results argues the hypothesis that individuals of this species recognize their neighbours and react less aggressively towards them. Moreover, our findings indicated that response to neighbours' calls follows a constant trajectory during the first or second half of the minute while the reaction towards foreigners is significantly losing intensity during the second half of the minute. The results suggest that the NSD and DEE are expressed in the Water Rail behaviour.

show abstract