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View Full Version : Aggression in Captive-Bred Ameca Splendens


Melody
Nov 30th 2006, 03:16 PM
I have observed just how aggressive Ameca Splendens can be and often wondered why they were classed as community fish. They know no fear, they will bite the tail of a Cichlid if the opportunity is there and community fish don't have a chance. In fact, they are so intent on definning fish, that I felt the need to label them as semi-aggressive when I sold them. Yet others who have owned them would swear that they were rarely aggressive.

I always thought that any wild creature kept in captivity would eventually become more 'tame' as the generations born in captivity increased. Apparently that isn't so with some fish. In this particular study, Ameca Splendens was the focus. It demonstrated that aggression is actually increased in captive breeding situations, and for far more reasons than one would first guess.

In this study, the fish were more aggressive when there was a dense population. People get the idea from Cichlids that increasing the numbers / overstocking, will reduce aggression - it doesn't. It distributes the aggression amongst a greater number of fish and may actually increase aggression levels overall.

Food appears to be a big factor - if they're not constantly foraging, they're more aggressive. I guess that could almost be classed as boredom...lol...but not quite.

You can combine these two factors, foraging and stocking levels, to create a more appropriate environment. A well furnished aquarium with lots of decorations, gravel, rocks, ornaments, etc, doesn't only provide cover for fish that are picked on and allow for the establishment of territories, but it also keeps the fish busy looking for food. Further on that point, try feeding very sparingly, and maybe use a lot of sinking foods that they have to find. Less fish, more furnishings, less food / different feeding regimes.

The importance here is the possibility of reintroduction to the wild, as in the case of endangered fish. Behaviorial divergence in captivity may make reintroduction impossible. In this case, aggression even interfered with breeding because the males were also aggressive to the females. The person whom I gave my Ameca Splendens to experienced a lack of breeding, so suddently that makes more sense. It can also make the fish too bold, as demonstrated by their suicidal nipping of big, mean Cichlids.

We can learn a lot from this study from several perspectives and apply the more indepth aggression explanations to other aggressive fish. If anyone (BLAINE...lol) has Ameca Splendens and the tanks to do a little experimenting, maybe we can figure out if this problem can be addressed by raising the fish differently, thus making reintroduction a more practical possibility. The hobby is responsible for keeping many endangered and threatened fish. Wouldn't it be wonderful if we could find a way to reintroduce them to their native habitat once the reasons for their endangerment were addressed?

The article that brought this to my attention is on the Practical Fishkeeping (http://www.practicalfishkeeping.co.uk/pfk/pages/item.php?news=1133) mag website. The people involved in the study are Jenny Kelley and Anne Magurran of the University of St. Andrews (Scotland) and the Constantino Macias Garcia of the Instituto de Ecologia (Mexico).

blainep
Dec 17th 2006, 12:03 AM
An interesting observation from my Ameca Slpendens, a while back I posted about one of my male Ameca Splendens.
He'd been beaten up pretty badly, I put him into his own tank and gave him some time to recover. He's pretty well fully recovered now.

His time alone has changed his personality considerably. My Amecas have never been particularly friendly, but my big male has become more 'domesticated'. He's at the glass right away when I come into the fishroom and he loves to play a little 'follow the finger' . That's a first from any Ameca Splenden I've ever had !

I'm worried now about putting him back in the mix, he's a friendly fish now, that's got 'beat me up' all over it. I may move his girlfriend back in with him and see how things go. I really don't need to start another tank of Splendens . I've got more than I need/want now.

I've noticed this behavior change in my Orange Tail Goodieds as well, upon their arrival in my home, they both showed alot of aggression towards each other. Shortly after separating them into their own tanks, both became friendly, wanting my attention.
They are back together again now, they don't show nearly as much aggression, but they aren't particularly friendly either.

Melody
Dec 17th 2006, 02:33 AM
Interesting. Maybe they're just too busy watching their back and fighting for dominance when they're in a tank with the rest?

I suppose if they were more crowded in the tank they came from, they would continue the behaviour in larger quarters, at least at first. Once they were given a chance to settle down, they might mellow.

Pure guesswork. It certainly makes one think anyway. You should try to track down contact information for the scientists involved in the study. They may be interested in the observation.:D