[Coral-List] Invasive Tilapia

[Abigail Moore]

Dear fellow listers

I also am most worried about Tilapia in brackish and salt water environments, thoguh this is the first time I have had any inkling others out there are also concerned. Research by a colleague has shown that the strains used in aquaculture here can withstand very high salinity, even above seawater, though growth is not optimal. 


These Tilapia are now being grown in tambak, brackish-water ponds originally intended for shrimp culture. Even without actual marine culture being introduced there is I feel a high risk of escape to the marine environment through the water inlet and outlet channels as well as through flooding events.

Knowing what Tilapia have done to endemic fish species in the lakes around here (e.g. Lindu and Poso) as well as to the fish fauna of some smaller less famous lakes, essentially outcompeting to the point of extinction or near extinction of native/endemic species, it is indeed very worrying.

With the current policy of Indonesia becoing the largest aquaculture producing country in the world by 2015, and ambitioius targets by local governments, it is going to be very hard to stop such activities as are already underway or prevent their spread, unless some compelling economic argument can be put forward. One related to fisheries or some other current economic activity, not tourism which is not a realistic alternative in most of our coastal areas, thoguh almost all have coral reefs, at the very least fringing reefs, arguably the most vulnerable to Tilapia take-over.

Best regards

Abigail

Abigail Moore
Sekolah Tinggi Perikanan dan Kelautan (STPL)
Kampus Madani

Jl Soekarno-Hatta

Palu 94118
Sulawesi Tengah
Indonesia



________________________________
 
Message: 1
Date: Sun, 27 Nov 2011 05:09:10 -0700
From: Paul Jarvis <carpenpan1 at yahoo.com>
Subject: [Coral-List] Invasive Species
To: "coral-list at coral.aoml.noaa..gov" <coral-list at coral.aoml.noaa.gov>
Message-ID: <3272808E-24A3-4776-BA6E-69DADC0A8787 at yahoo.com>
Content-Type: text/plain;    charset=us-ascii

Hi all,
I am a lurker here on the list.
I enjoy working with corals and am concerned with reef ecology. I am also a fisheries biologist. One of the lists I belong to is the yahoo tilapia mailing list.

This past week a thread was started there on the topic of saline full strength seawater tilapia production.

The concept of tilapia reproduction in seawater scares the heck out of me. As you can see this could be an ecological disaster. Tilapia are very fecund and would spread like a disease if ever encouraged to reproduce in full salinity seawater.

Just wanted to give the heads up on this before it gets out of hand.

According to listers on the tilapia list progress and success has already been achieved.

Perhaps you can do something before Pandoras box is opened.

Sincerely,
Paul Jarvis,
Fisheries Biologist, Aquaculturist