Introduction
Sea cucumber aquaculture in Latin America has garnered substantial interest in recent years with the addition of H. floridana as one of its potential species for cultivation as it can be produced with low tech methods for its resistance to varying conditions and its simple life cycle. However, locating its broodstock and mantaining it in land facilities can be a hurdle in certain areas, furthermore, up until now, the reproductive organisms tend to diminish their weight when kept in captivity, improvements in nutrition and holding protocols including environmental enrichment with different substrata can help keep broodstock in better conditions for longer times in captivity allowing their reuse for multiple years.
Methods
This work summarizes the results obtained in two experiments (1, 2) with the addition of different substrata to the broodstock holding tanks of H. floridana. Experiment 1: 30 organisms separated in 6 1x1x0.3m tanks, three treatments were used (A: no substrata, B: plastic mesh imitating the shape of seagrass, C: Rocks covering 25% of the area of the tank). Initial average weight was 72 g.
Experiment 2: upon finishing the first experiment, 9 tanks were set, with 5 organisms each, this time only with rocks creating 20, 40 and 60% cover of the area of each tank.
For both experiments, organisms were fed the same diet, photo identified and weighed every 15 (1) or 30 (2) days for three months (Figure 1)
Results and discussion:
In experiment 1, treatment C exhibited the largest overall growth (19.85 g), followed by no enrichment (16.93 g) and B (16.17 g), this represents a 21.48% weight increase in C, a 17.94% in B and an 18.88% for A. Final average weights were 92.41g (C), 90.11g (A) and 89.70g (B) (figure 2) Experiment 2 was a follow up of experiment 1, having shown that the best enrichment protocol was the presence of rocks, possibly due to the stimulation of a more natural behaviour, they would remain close or attached to a rock for long periods, only eating close, on, or around them, in this case results were comparable to experiment one but differences were not significant. Broodstock from all of the treatments were able to spawn in march 2024, having stayed in captivity for a year under multiple experimental conditions.
Conclusion
The use of rocks as environmental enrichment for H. floridana broodstock is a suitable method for improving their growth and maintenance in land facilities, aiding in their use for multiple years which reduces the reliance on wild stock.