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In many monogamous species, sexual selection often occurs through female mate choice, which is usually based on male characteristics such as size. However, the presence of a breeding site also might be equally or more valued than male size for substrate brooders. This study investigated the importance of a large mate versus the presence of a breeding site in the monogamous convict cichlid (Amatitlania siquia). If breeding sites are more valued than male size, then we predict that females will choose the male with breeding site regardless of his size. To test our hypothesis, males were confined to separate compartments with only one male receiving a breeding site, but females swam freely. In the experimental groups, one male was larger than the other, but both males were equal in size for the control group. Females significantly preferred small males with a breeding site more often than large males without a breeding site; thus, the presence of a breeding site seems to be more valued than male size by female convict cichlids. [ABSTRACT FROM AUTHOR]

In monogamous species that provide biparental care, partners with similar behavioural types generally have a better reproductive success than dissimilar ones. The pattern of assortative mating for behavioural type is thus often interpreted as resulting from a mate choice process. However, an alternative process is also possible when the partners become similar through postpairing adjustments (behavioural convergence). The disentanglement of these two nonexclusive mechanisms is an important evolutionary question. Only sexual selection based on behavioural similarity before pairing can explain the maintenance of the behavioural type variability. In a previous study, we reported the existence of behavioural convergence for aggressiveness between partners in convict cichlids Amatitlania siquia , a monogamous tropical fish. We tested herein the assumption of mate choice based on behavioural similarity for aggressiveness using either short-term binary choice or long-term group level pairing. Pairing was not based on behavioural similarity between potential partners. Choosing a behaviourally compatible partner is a complex task because it requires profiling the potential mates. Individuals would thus achieve higher fitness benefits from choosing a partner on more conspicuous criteria (such as size for instance) and then attempt to increase partner similarity by convergence after pairing. Sexual selection does not appear to drive the maintenance of aggressiveness type variability in convict cichlids. [ABSTRACT FROM AUTHOR]

In monogamous species, partner compatibility is a key factor influencing pairing and reproductive success. In pairs with biparental care, studies have mostly focused on behavioral compatibility because it is likely to encourage the coordination of parental care within pairs, leading to a better reproductive success. Behavior modulation, throughout the breeding season and as a function of the social context, is under the regulatory feedback control of endocrine mechanisms. From this link, the idea of hormonal partner compatibility as a key component of pair cohesion and maintenance has recently emerged. Here, we investigated the link between partner behavioral assortment and their hormonal response to the pairing context. We formed assortative and disassortative pairs of convict cichlids based on their behavioral type (proactive or reactive) and took hormone and fitness measurements. Testosterone, 11-ketotestosterone, 17β-estradiol and cortisol levels were measured from fish-holding water before and after pair formation. We found no relationship between the behavioral type of individuals and their pre-pairing hormone levels. Only the level of cortisol was affected by the partner but independently of its behavioral type. Reproductive success was not affected by the level of hormonal similarity within pairs, but we found that the variation in 11-ketotestosterone similarity between the isolated context and the pairing context was related to spawning size, and the variation in cortisol similarity to the number of fry. Behavioral compatibility does not reflect hormonal compatibility in the convict cichlid, but the relationship between reproductive success and the flexibility of hormonal similarity between partners suggests hormonal adjustment within pairs in this species. [ABSTRACT FROM AUTHOR]

Many monogamous species demonstrate size-assortative mating patterns within natural populations. To better understand the role of intersexual selection in this process, we examined the effect of male preference for female body size in the convict cichlid ( Amatitlania siquia ). We provided males with a choice between females that differed in size, relative to each other and in relation to the focal male. Based on previous work, we expected males to prefer the largest available female mates across all treatments. Surprisingly, males spent more time near the smaller of two available females, but only when the other female was larger than the male. Additionally, males spent little time with either of two potential female mates when both females were larger than the male. We hypothesized that while males might prefer the largest of available females, female behavior might limit males from acting on this preference. To test this, males were force paired with a smaller or larger female. Pair formation only occurred when the female was smaller than the male, and females that were larger than their male counterparts showed significantly more aggression when compared to smaller females. Together, these data suggest that in the absence of intrasexual competition, male mate preference for large females in convict cichlids might be limited by female aggression. [ABSTRACT FROM AUTHOR]

This study tested if convict cichlids (Amatitlania siquia) with prior predator experience could socially transfer their predator knowledge to their offspring. Prior to reproduction, pairs were assigned to either an experimental or control associative learning treatment, and given novel predator odour from a wolf cichlid (Parachromis dovii) paired with either alarm cue or water respectively. We hypothesized that upon re-exposure to the odour, experimental pairs would socially transfer their acquired predator knowledge to their naïve offspring, which in turn would exhibit antipredator behaviour. While fry from both treatment groups did not show a difference in shoal formation, there is some evidence to suggest a trend in the experimental group regarding parental ability to transfer information to offspring and influence shoal behaviour. When tested individually, experimental fry decreased their activity more than control fry in the presence of the predator odour. This study provides evidence of a unique form of predator learning between parents and offspring, suggesting that biparental care may also serve to provide offspring with information about the habitat into which they are born. [ABSTRACT FROM AUTHOR]

Interspecific patterns of space use in mobile animals have been the subject of considerable study, with allometric slopes often varying between 0.63 and 1.36. Both the slopes and intercepts of these relationships have been typically related to the energetic requirements of the focal animal, in relation to the amount of energy available in the environment. However, other explanations for these patterns are possible, including the ability of the focal animal to move about and/or defend a home range. To provide insight into this issue, we investigated the allometry of patch defence in convict cichlids, Amatitlania siquia, in a laboratory setting while controlling for energetic requirements. By manipulating the distance between two patches of food (0, 20, 40, 60, 80 and 95 cm), we estimated the maximum diameter of an ephemeral territory for 15 dominant fish that differed in body size by almost 40-fold. As expected, dominant fish were less able to defend and monopolize the food as the distance between the patches increased. Furthermore, larger fish were able to defend larger territories than smaller fish. The allometric slope of 1.18 in our study was remarkably similar to the interspecific slopes of home range or territory size in the literature for a broad range of vertebrate taxa. While there are likely multiple causes for the interspecific patterns of space use, our results suggest that the mobility of the defender is just as likely an explanation as energetic requirements. [ABSTRACT FROM AUTHOR]

Interindividual behavioural differences, consistent over time and across situations, are frequently related to differences in reproductive success, susceptibility to disease and competitive ability. The behavioural phenotype of a conspecific is likely to affect the outcome of a social interaction, so an individual must be able to accurately assess behavioural phenotypes in order to optimize behavioural responses during mate choice, cooperative relationships and agonistic interactions. However, behavioural assessment based on dyadic interactions in different contexts can be costly because it may require significant time, increase the risk of predation and often necessitates special cognitive abilities. Different colour cues are associated with different life history strategies in many species, so coloration might also correlate with behavioural phenotype. Thus, conspecifics could use coloration as a single cue for the mediation of social interactions. We investigated the relationship between personality and coloration in the monogamous, biparental convict cichlid. This species has black melanin-based stripes with interindividual variation in the intensity of these stripes. In addition, females have bright orange spots on their abdomens. Using repeatable measures of boldness, exploration and aggressiveness, we were able to define a behavioural syndrome and quantified the behavioural type of each individual. Behavioural types were predicted by colour traits. In particular, proactive individuals (more aggressive, bolder and quicker to resume behaviour after being startled) were more likely to be dark and, among females, have smaller orange areas. Our results support the hypothesis that coloration in the convict cichlid is related to personality. Thus, coloration could play an important role in mediating social interactions, allowing a quick and reliable assessment of conspecifics' behavioural types. [ABSTRACT FROM AUTHOR]

The convict cichlid, Amatitlania siquia, is a serially monogamous, bi-parental cichlid species native to Costa Rican rivers. Numerous field studies conducted in the Rio Cabuyo (Lomas Barbudal, Costa Rica) have provided a wealth of information regarding the behavioral ecology of this species. Recently a cichlid species that was previously not found in the Rio Cabuyo was identified as Hypsophrys nematopus. This influx of this non-native species provides an interesting ability to study the interactions of this potentially invasive species and to monitor the changes made by the native cichlid species. Over the course of several field seasons, I investigated the interactions between the native convict cichlid and the non-native cichlid. I surveyed the distribution of breeding pairs of both species and conducted behavioral tests to examine the interactions between the native and non-native species. I found an overall decline breeding pairs of both species over the course of the study. I found that both species were more aggressive to conspecific intruders and that female convict cichlids were aggressive to juveniles but males were not. These results provide important information concerning how native species interact with non-native species. It appears that the A. siquia population may experience a change in its reproductive behaviors due to the influx of H. nematopus. [ABSTRACT FROM AUTHOR]

Carotenoid-ornamented animals may transfer dietary carotenoid pigments to offspring as well as to their ornament and other competing physiological demands. If carotenoid supplementation increases offspring growth or survival, females should preferentially allocate supplemental carotenoids to offspring rather than ornamentation., We tested whether ornamented convict cichlid ( Amatitlania siquia) mothers increase carotenoid allocation to eggs with access to dietary carotenoid supplementation, and whether beneficial maternal effects of carotenoid supplementation were transferred to offspring., Maternal effects of carotenoid supplementation were found; offspring from mothers that ate carotenoids benefited in terms of growth and survival parameters compared with offspring from non-supplemented mothers. Contrary to predictions, maternal coloration was not sacrificed for fecundity: mothers maintained their coloration and integument carotenoids even though increased carotenoids in the maternal diet benefited the offspring. Furthermore, carotenoid supplementation did not increase the carotenoids deposited in eggs., This work is the first to show that indirect maternal effects of carotenoid supplementation increased the survival and growth of offspring. Indirect benefits may reduce the cost of carotenoid allocation to offspring, but the mechanism for how carotenoids support offspring development is still unknown. [ABSTRACT FROM AUTHOR]

Parental investment theory states that parents should contribute more to older offspring. Differences between the sexes also influence how each parent contributes to offspring in biparental species. Here, we examined a naturally occurring population of biparental convict cichlids in Costa Rica to determine how each parent cared for offspring during two distinct offspring development stages. Consistent with the predictions of the reproductive value hypothesis, we hypothesized that the levels of parental contribution would be relative to the value that each parent places on a brood. We predicted that female parents would contribute more than male parents because female convict cichlids have lower future reproductive success than males. Additionally, we predicted that both parents should contribute more to older offspring, either due to the young's increased susceptibility to predation (i.e., the vulnerability hypothesis) or because of the longer period of time parents have been interacting with older offspring (i.e., feedback hypotheses). This increase in investment by males should coincide with a change in the coordination of care between parents. Detailed observations of parental pairs in their natural habitat supported these predictions. Females contributed more to broods than males and were relatively unaffected by offspring age while males spent significantly more time with older, free-swimming fry. Additionally, males tended to leave younger offspring more than females did, and were more likely to do so consecutively with younger offspring. This suggests that the coordination of duties between parents changes as parental investment changes. Overall, these data support both the reproductive value and the vulnerability hypotheses, but not necessarily the feedback hypothesis. [ABSTRACT FROM AUTHOR]

We studied parental care behaviour in a field population of convict cichlids, Amatitlania siquia, a fish with biparental care of its free-swimming young (fry). We simulated catastrophic brood loss by removing all of the young from 26 broods of various ages. We recorded parental defence behaviour for 5min preremoval and three consecutive 5min postremoval intervals. We then returned all of the young and recorded 5min of parent–offspring reunion behaviour. Following brood loss, both parents defended the empty territory and searched for missing young. Females spent more time in the empty territory and performed more attacks in defence of the empty territory than did males. Females searched and defended a significantly larger area than males did. During the 15min fry-absent period, males increasingly spent more time away, whereas females maintained a constant level of investment in searching the brood area. Four of 26 males (15%) engaged in courtship with a new female within 15min of brood loss. Attacks to repel potential predators from the brood area declined in frequency over the 15min fry-absent period in both sexes. Standard length (age) of young was positively correlated with parental investment for females but not males. Number of young was positively correlated with parental investment for males but not for females. We conclude that post-brood-loss behaviours are search and recovery tactics that contribute to parental inclusive fitness in the event of incomplete brood predation. [Copyright &y& Elsevier]