aquaculture

Fish Farms Can Be Disease Accelerators

Much like terrestrial animal farms, fish farms are incubators for disease.

Last summer, more than half a million farmed salmon died from a sea lice outbreak in New Brunswick’s Passamaquoddy Bay. More than 250,000 died directly from the parasites, which attach themselves to the fish and feed on their skin, blood, and mucus, while another 284,000 were euthanized to try to contain the spread.

The outbreak, which affected two sites owned by Gray Group, a bankrupt aquaculture company that still had fish in its pens, was a “catastrophic loss,” says Matthew Abbott, an environmentalist who monitors Passamaquoddy Bay for the Conservation Council of New Brunswick. “Both sites were wiped out.” Read more in Hakai Magazine.

A creepy-crawly food revolution

Long considered pests, insects are now on the menu for farmed fish and poultry in Kenya and Uganda, where scientists are looking for cheaper, healthier ways to boost animal growth and develop the local economy.

Raising chickens or fish in Africa can be an expensive proposition. Most of the money goes into just keeping them fed, which accounts for 60 to 70 per cent of the cost of rearing the animals.

“Around here the high cost can discourage farmers from using high-quality feeds,” says Komi Fiaboe, an agricultural entomologist at the International Centre of Insect Physiology and Ecology in Nairobi, Kenya.

The feed’s most expensive component is protein, which usually comes from imported soybeans or a combination of imported and locally sourced fishmeal, and the cost of the latter has doubled in the past couple of years. So researchers in Uganda and Kenya are investigating a cheaper, local alternative that could reduce the price of feed while providing economic opportunities in the region: insects. Read more in Canadian Geographic.

 

Fish for Food

Exploring ways to get fish on the table in Bolivia.

People in Bolivia don’t eat much fish — among South American nations it has the lowest per-capita consumption — despite having a large number of lakes and rivers.

But local, sustainably sourced fish could be a good source of protein and help reduce food insecurity, as well as provide a new source of income for poor, rural populations. So the International Development Research Centre and Global Affairs Canada have teamed up with academics and NGOs in Canada and Bolivia on the Amazon Fish for Food project, which is trying to find ways to encourage the sustainable use of the country’s fish resources through fishing and aquaculture. Read more in Canadian Geographic.

The Living Lice Comb

IMG_7281Aquaculture adopts integrated pest management techniques for water-borne pests.

Like their land-based colleagues, fish farmers have to deal with pests and parasites that attack their animals. And like famers on land, they are looking for natural ways to deal with the pests that minimize the use of chemical treatments.

For salmon farms on the east coast of Canada, that means finding a way to fight the sea lice that can plague their open-water net pens. The aquaculture industry is now experimenting with using “cleaner fish,” such as cunner fish and lumpfish, to help control lice numbers, similar to how land-based integrated pest management techniques use natural predators to control pests. Read more in Hakai.

Blood in the water

Proteins from salmon blood can stop bleeding and alleviate pain.

In pens and hatcheries along the coasts of New Brunswick, Canada, and Maine, USA, young salmon are growing into adults that will soon grace dinner plates around the world. But these fish have much more to offer than just their delicious pink meat. If on-going research pans out, medicines derived from salmon blood could help save human lives and, possibly, mitigate chronic pain. Read more in Hakai.