Nine barriers, Hutovo Blato Nature Park, Bosnia and Herzegovina

Reopening the migratory routes from Hutovo Blato to the Adriatic Sea for endemic fish.

Introduction

The Neretva River, originating in the Bosnian and Herzegovinian mountains, creates a crucial delta along the eastern Adriatic coast, vital to numerous marine and avian species. At the centre of this ecosystem is the Hutovo Blato Nature Park, located 30 kilometres upstream from the Adriatic Sea. With more than 20 endemic species, 18 exclusive to the Adriatic watershed, the delta faces threats, with almost half of its species falling under various threat categories.

The project’s primary goal is to restore migratory routes from Hutovo Blato to the Adriatic Sea for endemic fish. Nine obsolete barriers impede this path, affecting species like the Neretvan nase, which resides in the Croatian part of the Neretva Delta but spawns upstream in Hutovo Blato. Removing these barriers will support the recovery of the Neretvan nase and other vulnerable fish species, addressing habitat destruction and contributing to their overall conservation efforts.

At a glance

Project typeDam removal (demolition)
Project statusLive
Removal dateAutumn 2024
CountryBosnia and Herzegovina
RiverJelimska Rječina, Šarčevac
Km to be opened3
Focal speciesHutovo goby, Neretva spinned loach, Dentex dentex, Alburnus alborella, Neretva nase, Dalmatian roach, eel
Websitewww.dinarica.org

Project context and opportunity

Over the past century, the Hutovo Blato wetlands have undergone significant changes due to extensive reclamation, irrigation, and hydropower development. This transformation resulted in the western part being isolated and converted for agriculture, while the southern section became a hydropower reservoir, leaving only the disrupted Derane as a natural area. These alterations have directly affected native and endemic fish species, with artificial barriers now obstructing vital migratory routes.

The project addresses nine artificial barriers located on the Jelimska Riječina and Šarčevac streams within the Hutovo Blato Nature Park. Its primary objective is to restore the migratory pathways for endemic fish such as Neretvan nase and Dalmatian roach. In 1999, commercial fisheries were banned, and the park’s management plan prioritises restoring and protecting endemic and native fish species. The Neretvan nase, once abundant and culturally significant for the local population, serves as a motivating factor for population recovery efforts.

The larger Neretva Delta, encompassing a network of natural and artificial waterways, has seen a decline in fisheries due to agricultural dominance. The project’s strategy of removing obsolete barriers presents a model that can be replicated across the wider Delta, unlocking hundreds of kilometres of water streams for fish migrations. This approach contributes to the conservation of globally threatened species like the eel, providing a valuable framework for sustainable practices in the region.

Project aims

The outdated fish-catching barriers in Hutovo Blato Nature Park obstruct migratory routes and hinder endemic fish spawning. Common carp’s reproduction is affected by lowered water levels, impacting their eggs attached to water plants. Derane Lake exhibits an overabundance of submersed plants during summers, threatening benthic species like the Hutovo goby and Neretva spinned loach. Dentex dentex and Alburnus alborella rely on wetlands as nursery grounds, while colder parts of Hutovo Blato are crucial for spawning grounds for Neretva nase and Dalmatian roach.

The project aligns with the Open River Programme’s mission, removing barriers on Jelimska Riječina and Šarčevac streams and reopening the route for endemic fish to reach the Adriatic Sea. Hutovo Blato, integral to the Neretva Delta ecosystem, faces modification with numerous irrigation barriers. This project, the first barrier removal in the Delta, is vital for the entire Neretva Delta’s biodiversity, requiring meticulous planning and environmental impact assessments to safeguard the sensitive habitat during and after removals.

Partners