Thank you.
I'm not all that familiar with tilapia production issues, so I won't be able to comment extensively on that particular question. But we can certainly get back to you with further information.
One comment I will make, though, is that stocking densities vary quite a bit among species—and I'm not sure, Alistair, if you know the figures for tilapia.
Behaviourally, different species of fish can perform and grow optimally at different stocking densities. Arctic char, for example, and I also believe tilapia, can grow naturally and perform quite well at quite high stocking densities, whereas certain fish, for example Atlantic salmon, don't perform as well at higher densities as some other species.
In terms of specific issues related to tilapia, my understanding is that there are the same types of issues in general around the performance of the fish in respect of their food conversion ratio, their growth, husbandry, and health management. These are the main concerns for tilapia.