Competition for Breeding Sites Between Monogamous Pairs of Convict Cichlids (Cichlasoma Nigrofasciatum): Asymmetries in Size and Prior Residence

Behaviour ◽  
1998 ◽  
Vol 135 (3) ◽  
pp. 261-267 ◽  
Author(s):  
◽  
◽  

AbstractWhen pairs of convict cichlids (Cichlasoma nigrofasciatum) were forced to compete for breeding sites, intruding pairs were not able to displace residents when the intruding pair was the same size as the resident pair. This prior resident asymmetry was over-ridden when each individual of the intruding pair was larger than its same-sex counterpart in the resident pair. When only one member of the resident pair (of either sex) was the same size as its same-sexed counterpart while its mate was smaller than its counterpart in the intruding pair, the residents were able to retain control of the breeding site. Thus, only one member of the resident pair needed to be similar in size to its same-sex counterpart for the residents to retain control. Single residents, of either sex, were either displaced by the intruding pair, or formed a pair with an intruder and then remained on the site.

Behaviour ◽  
2002 ◽  
Vol 139 (7) ◽  
pp. 861-873 ◽  
Author(s):  
Matthew Draud ◽  
Pamela Lynch

AbstractResearch on fighting has emphasized contests between individuals, typically males, but pairs also compete. Monogamous pairs of convict cichlids (Archocentrus nigrofasciatum) compete with other pairs for breeding sites in nature. We simulated such contests with competing pairs who differed in one or two of three possible asymmetries: body size, residency, and pair experience. In single-asymmetry experiments, larger pairs defeated smaller pairs, resident pairs defeated intruder pairs, and experienced pairs (those that had been together for 96 hours) defeated novice pairs (those that had been together for 48 hours). Thus, each of the three asymmetries was important in determining the outcome of contests. In further experiments, pairs had two contrasting asymmetries simultaneously. Larger pairs always defeated smaller pairs (15-25% difference in male standard length) even though the larger pair was inferior in one of the other asymmetries. When the two pairs were similar in size (standard length of males differed less than 6%), experienced intruder pairs defeated novice resident pairs nearly half the time. This is the first study to investigate the effects of pair experience on fighting ability. Although we predicted that experience might benefit pairs through improved coordination of their behaviour, behavioral measures such as time spent at the spawning site and pair digging behaviour showed no significant differences among groups. We posit that more experienced pairs fought harder for the breeding site because they were closer to spawning and the expected payoff for winning the breeding site was therefore higher. Finally, when both pairs were of similar size but differed in residence status and experience, there was more escalated fighting than in contests between size-disparate pairs; two possible interpretations of this result are discussed.


2020 ◽  
Vol 3 (5) ◽  
pp. 100-107
Author(s):  
Marina Camargo de Sousa ◽  
◽  
Julia Ronzani Vial ◽  
Rodrigo Hidalgo Friciello Teixeira ◽  
Andrea Cristina Higa Nakaghi ◽  
...  

Birds of the psittaciform order, composed by the Psittacidae and Loridae family have several characteristics making them more frequently kept as companion animals, promoting the increase of breeding sites in Brazil. The present study aimed to analyze the specificity and sensitivity of three different coproparasitological tests, Willis, Hoffman and Direto de feces, through statistical tests: Chi-Square and Kappa. 70 fecal samples of exotic parrots were collected from a commercial breeding site and these were submitted to the three tests, totaling 210 coproparasitological exams. Among the tests performed, 29,5% were positive for nematode eggs, cestodes and oocysts. Coproparasitological exams are inexpensive, have clinical importance, indicating the population of endoparasites and therapeutic treatments.


2013 ◽  
Vol 29 (2) ◽  
pp. 357-367 ◽  
Author(s):  
Onicio Batista Leal Neto ◽  
Elainne Christine de Souza Gomes ◽  
Fernando José Moreira de Oliveira Junior ◽  
Rafael Andrade ◽  
Diego Leandro Reis ◽  
...  

Schistosomiasis has expanded to the coast of Pernambuco State, Brazil, where there are frequent reports of Biomphalaria glabrata snails and human cases of the disease. This study analyzes factors related to schistosomiasis transmission risk in Porto de Galinhas. A one-year malacological survey was conducted to identify biological, abiotic, and environmental factors related to the host snail breeding sites. Data analysis used Excel 2010, GTM Pro, and ArcGis 10. A total of 11,012 B. glabrata snails were captured in 36 breeding sites, and 11 schistosomiasis transmission foci were identified. A negative correlation was found between breeding site temperature and snail density and infection rate, and a positive correlation with pH and salinity. The rainy season showed a positive correlation with snail density and infection rate. The study emphasizes the factors involved in the maintenance of schistosomiasis breeding sites, in light of persistence of this disease in Porto de Galinhas for more than 10 years.


2020 ◽  
Vol 3 (5) ◽  
pp. 100-107
Author(s):  
Marina Camargo de Sousa ◽  
◽  
Julia Ronzani Vial ◽  
Rodrigo Hidalgo Friciello Teixeira ◽  
Andrea Cristina Higa Nakaghi ◽  
...  

Birds of the psittaciform order, composed by the Psittacidae and Loridae family have several characteristics making them more frequently kept as companion animals, promoting the increase of breeding sites in Brazil. The present study aimed to analyze the specificity and sensitivity of three different coproparasitological tests, Willis, Hoffman and Direto de feces, through statistical tests: Chi-Square and Kappa. 70 fecal samples of exotic parrots were collected from a commercial breeding site and these were submitted to the three tests, totaling 210 coproparasitological exams. Among the tests performed, 29,5% were positive for nematode eggs, cestodes and oocysts. Coproparasitological exams are inexpensive, have clinical importance, indicating the population of endoparasites and therapeutic treatments.


2014 ◽  
Vol 71 (10) ◽  
pp. 1498-1507 ◽  
Author(s):  
Steven M. Clark ◽  
Jason B. Dunham ◽  
Jeffrey R. McEnroe ◽  
Scott W. Lightcap

The fitness of female Pacific salmon (Oncorhynchus spp.) with respect to breeding behavior can be partitioned into at least four fitness components: survival to reproduction, competition for breeding sites, success of egg incubation, and suitability of the local environment near breeding sites for early rearing of juveniles. We evaluated the relative influences of habitat features linked to these fitness components with respect to selection of breeding sites by coho salmon (Oncorhynchus kisutch). We also evaluated associations between breeding site selection and additions of large wood, as the latter were introduced into the study system as a means of restoring habitat conditions to benefit coho salmon. We used a model selection approach to organize specific habitat features into groupings reflecting fitness components and influences of large wood. Results of this work suggest that female coho salmon likely select breeding sites based on a wide range of habitat features linked to all four hypothesized fitness components. More specifically, model parameter estimates indicated that breeding site selection was most strongly influenced by proximity to pool-tail crests and deeper water (mean and maximum depths). Linkages between large wood and breeding site selection were less clear. Overall, our findings suggest that breeding site selection by coho salmon is influenced by a suite of fitness components in addition to the egg incubation environment, which has been the emphasis of much work in the past.


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