The Dilution Effect and Differential Predation Following Brood Adoption in Free-ranging Convict Cichlids (Cichlasoma nigrofasciatum)

Ethology ◽  
2010 ◽  
Vol 96 (3) ◽  
pp. 203-212 ◽  
Author(s):  
Brian D. Wisenden ◽  
Miles H. A. Keenleyside
Keyword(s):  
Dilution Effect ◽  
Cichlasoma Nigrofasciatum ◽  
Convict Cichlids ◽  
Differential Predation ◽  
Free Ranging

Aggressive behaviour among convict cichlid (Cichlasoma nigrofasciatum) fry of different sizes and its importance to brood adoption

1993 ◽  
Vol 71 (12) ◽  
pp. 2358-2362 ◽  
Author(s):  
Shannon A. Fraser ◽  
Brian D. Wisenden ◽  
Miles H. A. Keenleyside
Keyword(s):  
Dilution Effect ◽  
Young Measures ◽  
Size Difference ◽  
Biparental Care ◽  
Parental Rejection ◽  
Convict Cichlid ◽  
Free Swimming ◽  
Cichlasoma Nigrofasciatum ◽  
Convict Cichlids ◽  
Differential Predation

Convict cichlids (Cichlasoma nigrofasciatum) exhibit extended biparental care of their young. Parents will adopt unrelated (foreign) conspecific young of similar size to or smaller than their own but reject larger foreign young. Adoption of smaller foreign young may benefit the parents by reducing loss of their own young to predators by the dilution effect, which may be enhanced by differential predation on the smaller young. Another factor influencing adoption is that larger foreign young may pose a direct predatory threat to the host parents' young. Measures of aggression among free-swimming young of different sizes showed that there was at least a 1 mm (standard length) size difference before larger young attacked smaller, a 3 mm difference before injury occurred, and a 4–5 mm difference before predation occurred. Parents were initially more discriminating than their young with respect to the size of foreign young accepted. As their young grew and became stronger swimmers, parents less actively rejected larger foreign young; however, they continued to reject them before they were large enough to pose a direct predatory threat. Parental rejection of relatively large foreign young is therefore based more on protecting their own young from differential predation than from aggression by larger adoptees.

Reproductive behaviour of free-ranging convict cichlids,Cichlasoma nigrofasciatum

1995 ◽  
Vol 43 (2) ◽  
pp. 121-134 ◽  
Author(s):  
Brian D. Wisenden
Keyword(s):  
Reproductive Behaviour ◽  
Cichlasoma Nigrofasciatum ◽  
Convict Cichlids ◽  
Free Ranging

Factors affecting reproductive success in free-ranging convict cichlids (Cichlasoma nigrofasciatum)

1994 ◽  
Vol 72 (12) ◽  
pp. 2177-2185 ◽  
Author(s):  
Brian D. Wisenden
Keyword(s):  
Growth Rate ◽  
Reproductive Success ◽  
Stream Habitat ◽  
Factors Affecting ◽  
Cichlasoma Nigrofasciatum ◽  
Brood Survival ◽  
Spawning Site ◽  
Convict Cichlids ◽  
Significant Difference ◽  
Free Ranging

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.

The influence of predators on adoption behaviour in adult convict cichlids (Cichlasoma nigrofasciatum)

1996 ◽  
Vol 74 (6) ◽  
pp. 1165-1173 ◽  
Author(s):  
Shannon A. Fraser
Keyword(s):  
Predation Risk ◽  
Alloparental Care ◽  
Convict Cichlid ◽  
Cichlasoma Nigrofasciatum ◽  
Upper Limit ◽  
Convict Cichlids ◽  
Hypothesis Model ◽  
Differential Predation ◽  
High Predation ◽  
Brood Guarding

The adoption of unrelated young by brood-guarding convict cichlid (Cichlasoma nigrofasciatum) parents is influenced by several factors. Three of these are the risk of intrabrood aggression, the risk of differential predation of their own young, and the trade-off between the benefits of brood dilution and the costs of differential predation. This study introduces the "adoptable fry size hypothesis" model, which synthesizes the findings of earlier studies on each of these factors and details the range of adoptable fry sizes that increase foster brood survival across fry development. The influence of predation risk on the behaviour of parents toward foreign fry of different sizes was examined. Brood-guarding adults approached and mouthed at foreign fry larger than the upper limit of the model least often, but bit at them most often, thus excluding them. As host fry size increased, the number of behaviours directed at foreign fry decreased. Predator number did not significantly influence the size of foreign fry toward which the adults directed their behaviour. However, the overall frequency of these behaviours increased with increasing predator number, confirming previous studies suggesting that alloparental care is motivated by high predation risk.

Factors influencing pairbond stability in convict cichlids (Cichlasoma nigrofasciatum)

1997 ◽  
Vol 39 (2) ◽  
pp. 161-176 ◽  
Author(s):  
Jürg Lamprecht ◽  
Thomas Rebhan
Keyword(s):  
Cichlasoma Nigrofasciatum ◽  
Factors Influencing ◽  
Convict Cichlids

Changes in Aggressive Interaction in Adjacently Territorial Convict Cichlids (Cichlasoma Nigrofasciatum): a Study of Habituation

Behaviour ◽  
1971 ◽  
Vol 40 (1-2) ◽  
pp. 43-54 ◽  
Author(s):  
Michael J. Herz ◽  
Harman V.S. Peeke ◽  
James E. Gallagher
Keyword(s):  
Ecological Niche ◽  
Prolonged Exposure ◽  
Continuous Exposure ◽  
Aggressive Interaction ◽  
Minute Exposure ◽  
Cichlasoma Nigrofasciatum ◽  
Uniform Pattern ◽  
Convict Cichlids ◽  
Stimulus Source ◽  
Exposure Conditions

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.

Technique for Tagging Small Fish with I131 for Evaluation of Predator–Prey Relationships

1978 ◽  
Vol 35 (1) ◽  
pp. 143-145 ◽  
Author(s):  
Gerard J. FitzGerald ◽  
Miles H. A. Keenleyside
Keyword(s):  
Content Analysis ◽  
Key Words ◽  
Stomach Content ◽  
Stomach Content Analysis ◽  
Small Fish ◽  
Short Term ◽  
Predator Prey ◽  
Cichlasoma Nigrofasciatum ◽  
Quantitative Studies ◽  
Convict Cichlids

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

The Effects of a Trade-Off Between Foraging and Brood Defense On Parental Behaviour in the Convict Cichlid Fish, Cichlasoma Nigrofasciatum

Behaviour ◽  
1992 ◽  
Vol 120 (1-2) ◽  
pp. 123-138 ◽  
Author(s):  
Robert W. Rangeley ◽  
JEAN-GUY J. Godin
Keyword(s):  
Cichlid Fish ◽  
Net Energy ◽  
Activity Levels ◽  
Parental Effort ◽  
Trade Off ◽  
Cichlasoma Nigrofasciatum ◽  
Investment Theory ◽  
Convict Cichlids ◽  
Brood Defense ◽  
Energy Gains

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.

Weight asymmetry and sequential assessment in convict cichlid contests

1993 ◽  
Vol 71 (3) ◽  
pp. 475-479 ◽  
Author(s):  
Marten A. Koops ◽  
James W. A. Grant
Keyword(s):  
Weight Ratio ◽  
Assessment Model ◽  
Convict Cichlid ◽  
Cichlasoma Nigrofasciatum ◽  
Convict Cichlids ◽  
Temporal Overlap

We staged contests between pairs of convict cichlids (Cichlasoma nigrofasciatum) that varied in weight ratio (larger/smaller) from 1.02 to 4.86 to test the predictions of the sequential assessment model. As predicted, contests proceeded in a consistent sequence of behaviour (lateral display, biting, mouth wrestling, and circling), the duration of contests was inversely correlated with weight ratio, and the duration of complete phases of behaviour was independent of weight ratio (a phase is complete if the contest escalates to the next behavioural phase). However, there was temporal overlap in the occurrence of different behaviour patterns and variation in the duration of contests that are not explained by the model. Nevertheless, the structure of convict cichlid contests is consistent with the logic of the sequential assessment model.

Sign in / Sign up

Export Citation Format

Share Document