Belize Association of
Most of the shrimp farms in Belize are located around the Placencia Lagoon.
Shrimp farms pose a potential threat to the Lagoon primarily through eutrophication from nutrient rich shrimp farm run-off into the Lagoon. Eutrophication means the water is changed from oxygen rich/nutrient poor water that promotes the growth of marine life, to oxygen poor/nutrient rich waters in which marine life accustomed to oxygen rich/nutrient poor water cannot survive.
(Run-off from shrimp farms can also include insecticides, pesticides, shrimp feed, shrimp waste and antibiotics. However, according to tests performed by the Belize Agricultural and Health Authority (BAHA), Belize shrimp farmers do not use antibiotics, insecticides or pesticides in their shrimp food. In countries which allow the use of antibiotics in shrimp food, the antibiotics in run-off can inject antibiotics into the food chain, increasing the risk of bacteria becoming immune to the antibiotics creating the risk that antibiotics won't work when we need them.)
Aside from risks posed by antibiotics and pesticides/insecticides where their use is allowed, eutrophication, which is a risk present in all shrimp farm run-off that is not properly treated, can cause suffocation of marine life if the oxygen is reduced so much that marine life can't breathe.
Eutrophication from shrimp farm run-off combined with dredging in the Placencia Lagoon in the past has adversely affected the Lagoon's sea grass beds, almost completely killing all of the sea grass in some parts of the Lagoon. The shrimp farm run-off causes the growth of algae, which makes the water less clear, reducing the sunlight that gets to the seagrass beds -- the sunlight that the seagrass needs to live and thrive. (Loss of sea grass beds in Placencia Lagoon linked to effluent from Belize shrimp farms.)
Loss of sea grass in the Lagoon previously caused the Lagoon to be abandoned by most of the dolphins and manatees that used to live and breed there. (The Placencia Lagoon is one of three areas in Belize where researchers found Halophilla baillonii, a sea grass particularly favored by manatees. Almost all of this sea grass disappeared at one time.)
Loss of sea grass beds also reduced the number of fish and other marine life such as rays that formerly inhabited the Lagoon when the abundant sea grass was used for shelter and food for juvenile fish and other marine life.
But, there's hope. Most of the shrimp farms on the Placencia Lagoon have significantly reduced their run-off and effluent load through voluntary efforts and sea grasses are rapidly regrowing in the Lagoon, and we are witnessing the return of manatees, dolphin and fish.
Also, mangroves in and around the Placencia Lagoon are not at risk from shrimp farms because all shrimp farms in the area were built behind the mangrove perimeter. In fact, the mangroves are used to filter the run-off from most of the farms, unfortunately proving that mangroves alone are not adequate to clean shrimp farm run-off to the extent needed to prevent the run-off from harming the Lagoon eco-system.
Large international organizations such as the World Wildlife Fund and the Environmental Defense Fund have recently promoted shrimp "certification" for shrimp produced by farms that have met certain environmental requirements designed to reduce the impact of shrimp farms on tropical environments.
Several shrimp farms around the Placencia Lagoon have received certifications from these and other shrimp certification programs.
The problem with these certification programs is that once a farm is certified, it's not clear if, or how often, the certifying organization re-checks to make sure farms are continuing the more environmentally friendly farming practices. While the local Placencia and Seine Bight communities could be engaged to monitor the farms to ensure continuing compliance, this type of community engagement has not been included as a component of certification. However, local Placencia shrimp farms do seem to be receptive to community monitoring and a "Lagoon Committee" that would oversee the health of the Placencia Lagoon.
Some organizations such as the Mangrove Action Project also see the certification programs as dangerous because they lull consumers into believing their shrimp consumption is not harming the environment, when it actually is. These organizations believe the only real solution is for people to simply eat fewer shrimp -- or no shrimp at all.
Assessment of the Ecological Impacts of Two Shrimp Farms in Southern Belize, Sean Ledwin
The Placencia area currently has no caged fish farming. An EIA was submitted for a caged fish farm at the Lark Caye Range, but the developer withdrew the proposal after it was met with exceptionally strong community opposition.
Fish Farm Proposal: PCSD Response
Peninsula Citizens for Sustainable Development