Factors affecting mate desertion by males in free-ranging convict cichlids (Cichlasoma nigrofasciatum)

1994 ◽  
Vol 5 (4) ◽  
pp. 439-447 ◽  
Author(s):  
B. D. Wisenden
1994 ◽  
Vol 72 (12) ◽  
pp. 2177-2185 ◽  
Author(s):  
Brian D. Wisenden

This study examines the effect of parent size, fry growth rate, and habitat-related brood predation pressure on two measures of reproductive success (percent brood survival and fry number at independence from their parents) of free-ranging convict cichlids (Cichlasoma nigrofasciatum). Four populations in Costa Rican streams were studied, two in "pool" habitat and two in "stream" habitat. The number of fry that emerged from the spawning site (as free-swimming young) was positively correlated with female standard length (SL) for sites with a relatively wide size range of breeding females. SL of males had no effect on fry number at emergence, nor did size of either parent affect the probability of a brood reaching fry independence. Large parents reared more fry to independence than small parents in stream habitat but not in pool habitat. There was a significant difference among sites in fry number at emergence but not at independence (mean = 27 fry), suggesting a maximum number of fry that two parents can economically defend. Fry growth rate had no effect on either measure of reproductive success. Reproductive success was largely determined by the effect of habitat. Adult Cichlasoma dovii in pool habitat may have reduced mean brood survival from 47% (n = 126 broods) in stream habitat to 14.9% (n = 141 broods) in pool habitat. Predators such as juvenile C. dovii may be more effective in the dim ambient light in pool habitat, overwhelming the effect of parent size on brood defence.


2021 ◽  
Vol 30 (3) ◽  
pp. 331-339
Author(s):  
DS Machado ◽  
AFF Bragança ◽  
IC Travnik ◽  
AP Rossi ◽  
AC Sant'Anna

A need exists for research that contributes to estimating the risk factors associated with the management of outdoor cats (Felis silvestris catus) and addresses the lack of such surveys in Brazil and other Latin American countries. With this in mind we aimed to: i) identify the causal factors affecting the practice of owners allowing their cats to roam freely and; ii) evaluate potential welfare risks associated with the allowance of outdoor access, based on cat owners' reports. An online questionnaire consisting of 25 questions was answered by 8,485 Brazilian cat owners and logistic regression models used to obtain odds ratios. A number of the factors significantly related to owners allowing their cats to have outdoor access were unneutered cats, the manner in which the cat was acquired, residence in rural areas, the number of cats owned, the presence of other pets in the house, younger owner age, owner declaration of not being responsible for the cat, owner perception about the role of the cat in the house, owner knowledge about cats' potential for transmitting diseases, a lack of knowledge about zoonoses, and a lack of knowledge regarding toxoplasmosis. The practice of allowing outdoor access was associated with significantly higher odds of owners reporting several welfare issues, such as frequent flea contamination, sporotrichosis, going missing, poisoning, mistreatment, and accidents. We conclude that the practice of allowing outdoor access, as reported by 37.1% of our respondents, may result in risks to feline welfare. Increasing public awareness through campaigns that highlight the risks associated with outdoor access would improve feline management practices and welfare.


2008 ◽  
Vol 70 (11) ◽  
pp. 1023-1032 ◽  
Author(s):  
Joanna M Setchell ◽  
Tessa Smith ◽  
E Jean Wickings ◽  
Leslie A Knapp

Behaviour ◽  
1971 ◽  
Vol 40 (1-2) ◽  
pp. 43-54 ◽  
Author(s):  
Michael J. Herz ◽  
Harman V.S. Peeke ◽  
James E. Gallagher

AbstractPairs of male Convict Cichlids (Cichlasoma nigrofasciatum) were isolated from each other and then exposed in adjoining territories under one of two exposure conditions, either daily 20 minute exposure for 38-44 days or a massed continuous exposure for 24 or 28 hours. The incidence of biting and the duration of chin display for each fish was recorded. The duration of the chin display described a near uniform pattern of attenuation for both exposure conditions. The waning of the biting response was evident but it was more variable than the chin display. It was concluded that these behaviors both tend to habituate with repeated or constant exposure to the same stimulus source and that prolonged exposure facilitates the habituation of aggressiveness between territorial neighbors, thus promoting peace in a particular ecological niche.


1978 ◽  
Vol 35 (1) ◽  
pp. 143-145 ◽  
Author(s):  
Gerard J. FitzGerald ◽  
Miles H. A. Keenleyside

Experiments to test the feasibility of using radioactive I131 as a technique for evaluation of conspecifïc predation on fry by adult convict cichlids (Cichlasoma nigrofasciatum) are described. The technique is useful for short-term quantitative studies of predator–prey interactions where it is not possible to observe and quantify predation directly or where stomach content analysis of adults is not feasible. Key words: radioactive tagging, predator–prey interactions, Cichlasoma nigrofasciatum


Behaviour ◽  
1992 ◽  
Vol 120 (1-2) ◽  
pp. 123-138 ◽  
Author(s):  
Robert W. Rangeley ◽  
JEAN-GUY J. Godin

AbstractParental convict cichlids, Cichlasoma nigrofasciatum, responded to the presence of a potential brood predator by decreasing net energy gains (food intake decreased and energy expenditure increased) while increasing parental effort (large allocation of time to brood defense). These behaviours are important factors in the life-history trade-off between current and future reproductive investments. The allocation of energy into defense behaviours and elevated activity levels, combined with a voluntary reduction of food consumption, represent an investment in the current brood which could (in nature) reduce future reproduction. Contrary to parental investment theory predictions, consistent increases in parental effort with brood age were not evident.


2005 ◽  
Vol 21 (2) ◽  
pp. 107-119 ◽  
Author(s):  
Yuji TAKENOSHITA ◽  
David SPRAGUE ◽  
Nobusuke IWASAKI

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