The endangered Mexican fish Zoogoneticus tequila represents a new challenge for scientists: its biology, still unknown, could perhaps explain the reason for its extremely low consistency in natural environments. An experimental setting was prepared where four pairs of young Z. tequila from the only Italian colony were breed in two different tanks, biotopic and enriched. Because the captivity could promote behavioral traits that can be maladaptive in the wild, we carried out a random schedule for food dispensing in both groups, then obliging the fishes to actively look for it. During the experimental protocol, the observations were carried out for ten min. three times a day. Preliminary results showed a similar agonistic behavior in both the case study (biotopic) and the enriched tank. Aggressive behavior was extremely low and, although inter-male interactions were more unstable, no injuries were observed among the animals, apart from an episode of cannibalism in the biotopic tank realized by a female towards a young. The analysis of reproductive performance did not show differences between the two groups. The behaviour of animals in stressful situation were also recorded, namely the encounter with a male displaying enhanced sexual characters, such as the yellow-orange tail border, or with a predator. The behavioral response toward the male were more noticed in the enriched tank, where flicks of the tail and display of the fins were recorded compared to the biotope. On the other hand, the predator snake Thamnophis sp elicited an innate flight response in both the experimental conditions and in both sexes. All together those results seem to encourage the breeding of Z. tequila in captive condition, although more studies on the cognitive skills of the species should be carefully evaluated before its reintroduction in the natural environment.[...]
E' possibile la reimmissione in naura del Goodeide Messicano Zoogoneticus tequila? sstudio su soggetti allevati i ambiente bioopico ed arricchito
BERNABO', NICOLA;LUCIDI, Pia
2009-01-01
Abstract
The endangered Mexican fish Zoogoneticus tequila represents a new challenge for scientists: its biology, still unknown, could perhaps explain the reason for its extremely low consistency in natural environments. An experimental setting was prepared where four pairs of young Z. tequila from the only Italian colony were breed in two different tanks, biotopic and enriched. Because the captivity could promote behavioral traits that can be maladaptive in the wild, we carried out a random schedule for food dispensing in both groups, then obliging the fishes to actively look for it. During the experimental protocol, the observations were carried out for ten min. three times a day. Preliminary results showed a similar agonistic behavior in both the case study (biotopic) and the enriched tank. Aggressive behavior was extremely low and, although inter-male interactions were more unstable, no injuries were observed among the animals, apart from an episode of cannibalism in the biotopic tank realized by a female towards a young. The analysis of reproductive performance did not show differences between the two groups. The behaviour of animals in stressful situation were also recorded, namely the encounter with a male displaying enhanced sexual characters, such as the yellow-orange tail border, or with a predator. The behavioral response toward the male were more noticed in the enriched tank, where flicks of the tail and display of the fins were recorded compared to the biotope. On the other hand, the predator snake Thamnophis sp elicited an innate flight response in both the experimental conditions and in both sexes. All together those results seem to encourage the breeding of Z. tequila in captive condition, although more studies on the cognitive skills of the species should be carefully evaluated before its reintroduction in the natural environment.[...]I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
