Female habitat choice as a determinant of the reproductive success of the territorial male marine iguana (Amblyrhynchus cristatus)

The Marine Iguana ( Amblyrhynchus cristatus ) is a species endemic to the Galapagos Islands. It lives in large aggregations along the rocky shore lines throughout the archipelago. It is the only iguanid specialized for feeding on marine algae, which they crop at low tide from the exposed rocks or even by diving down to the bottom of the sea. The animals are extremely gregarious and sometimes hundreds of iguanas bask on the lava rocks in bodily contact with each other. Besides this mutual attraction, however, no specific forms of social interaction like grooming, mutual feeding rituals, etc. are to be observed. This is in striking contrast to the social behaviour of birds and mammals which use such patterns for bond formation. These bond-forming behaviour patterns are mainly derivates of maternal behaviour, which seem to be preadapted for this purpose. Reptiles lack maternal behaviour and this may in part explain their inability to form a closer bond between adults.

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Lactic Acid Production during Field Activity in the Galapagos Marine Iguana, Amblyrhynchus cristatus

Physiological Zoology ◽

10.1086/physzool.53.2.30152578 ◽

1980 ◽

Vol 53 (2) ◽

pp. 157-162 ◽

Cited By ~ 13

Author(s):

Todd T. Gleeson

Keyword(s):

Lactic Acid ◽

Acid Production ◽

Lactic Acid Production ◽

Amblyrhynchus Cristatus ◽

Field Activity ◽

Marine Iguana

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Prior Breeding Success Affects Return Rates of Territorial Male Ovenbirds

The Condor ◽

10.1093/condor/105.1.73 ◽

2003 ◽

Vol 105 (1) ◽

pp. 73-79 ◽

Cited By ~ 4

Author(s):

Paul A. Porneluzi

Keyword(s):

Reproductive Success ◽

Breeding Success ◽

Territorial Male ◽

Breeding Dispersal ◽

Seiurus Aurocapillus ◽

Return Rates ◽

Breeding Experience ◽

A Site

AbstractI examined the hypothesis that male Ovenbirds (Seiurus aurocapillus) make breeding dispersal decisions based on prior breeding experience at a site. I determined the reproductive success of color-banded male Ovenbirds at sites in fragmented and unfragmented landscapes in Missouri from 1992–1995. I documented which individuals returned and I recorded their reproductive success upon return as well as the success of birds new to each plot. I obtained similar results in both landscapes. Males with different histories of reproductive success returned at different rates. Only 2 of 22 males that were paired but failed to raise young returned in the following year, whereas the return rates of unpaired males (41%, n = 37) and males that successfully raised young (54%, n = 57) did not differ significantly (P = 0.19). The patterns were more consistent with the hypothesis that return rates were due to decisions about dispersal rather than difference in survival of individuals in these groups.El Éxito Reproductivo Previo Afecta Índices de Regreso de Machos Territoriales de Seiurus aurocapillusResumen. Examiné la hipótesis de que individuos de Seiurus aurocapillus hacen decisiones de dispersión reproductiva basadas en las experiencias reproductivas previas en un sitio. Determiné el éxito reproductivo de machos con anillos de color en lugares en terrenos fragmentados y no fragmentados de Missouri entre 1992 y 1995. Documenté cuáles individuos regresaron y su éxito reproductivo al regresar, y también el éxito de pájaros nuevos en cada sitio. Obtuve resultados semejantes en ambos paisajes. Los machos con historias de éxito reproductivo diferentes presentaron índices de regreso diferentes. Solamente 2 de 22 machos apareados que no produjeron cría volvieron al año siguiente, mientras que los índices de regreso de machos no apareados (41%, n = 37) y de los machos que produjeron crías exitosamente (54%, n = 57) no difirieron significativamente (P = 0.19). Los patrones concuerdan más con la hipótesis de que los índices de regreso se deberieron a las decisiones de dispersión y no a la diferencia de supervivencia de individuos en estos grupos.

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