Climate change poses threat to fishing in coast

Fisheries is undoubtedly the lifeline of the coast’s economy and a source of livelihood for thousands. It is also an important pillar of the national economy as it earns the national coffers billions a year.

However, the sector now faces several threats including over-fishing, climate change and rising human population. These factors have played a role in diminishing the coral reef ecosystem on which the sector depends.

“The increase in sea water temperatures as a result of climate change leads to coral bleaching and death of some of them,” says Edward Kimakwa scientist with World Wide Foundation (WWF).

Coral reefs are a ridge of rock in the sea formed by the growth and deposit of coral and mainly act as a breeding ground for fish.

Mr Kimakwa says global warming led to a serious bleaching of the reefs in 2008 and 2016. Some of the worst bleaching events were experienced in 1998 in which between 50 per cent and 90 per cent of coral cover was lost.

Director General of Fisheries Suzan Imende says the government has had to intervene at the coast in order to preserve the coral reefs that are in danger of being completely wiped out.

“We have had to stop fishing in some areas and train fishermen how to grow the live coral reefs in order to restore them,” said Ms Imende.

The areas that have been restricted to fishing are sections of the ocean with rich cover of coral reefs. The aim, says the scientist, is to stop human interference with the reefs.

Historically, management of coral reefs in Kenya has been the domain of the central government, with a network of four marine parks and six marine reserves — partially protected, allowing traditional fishing — under the management of Kenya Wildlife Service (KWS).

In areas not managed by KWS, fishing has grown relatively unregulated and unmanaged. Some specific prohibitions exist, such as against spearguns and beach seines. Buffer zones have also been created to keep trawlers at a certain distance from the shore.

Fishermen who use larger nets that go deeper into the water tend to interfere with coral reefs as the fishing gears pull them down when they move.

The Western Indian Ocean Reef Status Report shows the impact of human activities in Kenya and other countries such as Comoros, France, Kenya, Madagascar, Mauritius, Mozambique, Seychelles, South Africa and Tanzania.

“Western Indian Ocean coral reefs experienced widespread coral bleaching during the first global coral bleaching event in 1998, in which 30-50 per cent of corals were estimated to have died,” says the report.

“In the face of increasing direct human impacts and predicted climate-change bleaching events, there is an urgent need to anticipate and prevent undesirable regime shifts and, conversely, to reverse shifts in already degraded reef systems.”

It adds: “Such challenges require a better understanding of the primary human and natural drivers that undermine reef ecological status and fishery resources in order to plan for effective conservation and management of coral reefs,” it adds.

The number of fishers has increased over the years due to other drivers, over-exploitation of targeted resources has occurred leading to declines in individual catches, such as of serranids (groupers), lutjanids as well as other scavengers, and rabbitfish.

This is compounded by migration from inland to coastal areas, attracted by employment in maritime trade, fisheries, agriculture, mining and tourism.

Despite this gloomy outlook, scientists say all is not lost. A number of initiatives to revive the ecosystem are ongoing.

Experts say some of the challenges can be dealt with locally but others such as climate change should need be addressed globally. They warn that greenhouse gas emissions should be reduced sharply to meet the Paris Agreement levels of limiting global warming to below 1.5 degrees Celsius in order to save the reefs.

Community-based reef restoration programmes, which comprise coral transplanting and use of artificial reefs, as done in South Coast (Wasini), has proved to be effective.

“The restoration programme that involves transplanting of coral reefs in some parts of coastal Kenya have given us hope that we can restore this ecosystem through such activities,” says Mr Kimakwa.

The restoration projects have improved fish density by two folds within one year of project implementation.

Experts say community-based protection of coral reefs in partnership with government fisheries should be enhanced, pointing out the need for enabling legislation to ensure their long-term sustainability.

This story was supported by the African Academy of Science