Minister visits Ria Formosa seahorse sanctuary

Seahorse populations are recovering after being decimated in the last decade due to illegal fishing

Portugal’s Environment Minister Duarte Cordeiro was in the Algarve last week as part of the government’s two-day tour of the region, having set aside some time to visit the Ria Formosa seahorse sanctuary near Culatra Island.

Maritime signalling works were recently carried out at the sanctuary and are described as an “essential step” for estuary users to “know where navigation is forbidden, thus guaranteeing a more effective preservation of seahorses and their natural habitat at Ria Formosa,” says the Regional Board of the Nature and Forest Conservation Institute (ICNF).

The signalling was carried out by ICNF with the help of the Algarve Sea Science Centre (CCMar) and the Almancil International Rotary Club.

As ICNF points out, the Ria Formosa seahorse population has suffered a great decline in the last decade due to human activity.

Illegal fishing is one of the main reasons as seahorses are much sought after by the Asian market and a popular ingredient in traditional Chinese medicine.

Minister visits Ria Formosa seahorse sanctuary

This illegal activity started being detected between 2013 and 2015 and “led to a sudden decrease in populations” which were left “totally exposed” to the trawling method used.

This method also had an “indirect impact on the bottom of the estuary,” which affected the habitats of the seahorses, such as the underwater prairies of Ria Formosa.

Underwater sound pollution and aggradation (an increase in land elevation due to the accumulation of sediment) near breakwaters were also identified as issues affecting the local seahorse population.

In order to prevent the extinction of the estuary’s seahorses, a special group – with an exceptionally long name (Grupo para a Salvaguarda e Conservação das Populações de Cavalos Marinhos da Ria Formosa, or GSCPMRF) – was set up, featuring all the local and national institutions with the power to help mitigate the damage already done and propose measures to save the local seahorses.

One of the first measures implemented was the creation of sanctuary areas for the seahorses – one in Culatra and another in Geada – to not only provide safe zones for this species but also test whether the measure is effective and if more sanctuary areas are needed.

These efforts have proven successful, as monitoring campaigns in 2022 showed a “significant increase of the population of these species,” said to be six times higher than in 2020 and 2021.

While the number of seahorses was still very low in some of the 25 locations monitored, the increase was substantial in others, ICNF says.

“This allowed us to register a significant global increase in the abundance of seahorses observed in Ria Formosa,” it adds.

The institute is predicting a “promising future” for the local seahorse population, although it says that it is vital to continue monitoring in order to have updated information and act accordingly.

By Michael Bruxo
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