Project

Wedgefish habitat mapping and conservation in Java

Photo © Antika Milata

Species

Rays & Skates

Year funded

2026

Status

Active

Project types

Conservation
Research

Affiliation

Tuban Mermang Conservation

Description

In Tuban, East Java, many small wedgefish are being landed by local fishers. Antika is concerned that this might indicate the presence of a nursery ground for these Critically Endangered rays. Her response? To combine science, community engagement and policy advocacy for species in decline because of intense pressure from fishing with trawls, seine nets and bottom-set gears. Antika is mapping critical habitats, monitoring catch trends and promoting safe release practices to reduce mortality and support stronger management. By identifying key wedgefish habitats and working directly with fishing communities, this project will help protect these species, safeguard local ecosystems and create a foundation for sustainable fisheries.

Read project details

Wedgefish habitat mapping and conservation in Java

Antika Milata Rizka

Project leader

About the project leader

My passion for conservation began while I was studying for a Bachelor’s degree in aquatic resources management at IPB University, Indonesia, when I was frequently involved in projects on coastal ecosystems and community engagement. These early experiences convinced me that effective conservation must strike a balance between ecological protection and the realities of people’s livelihoods.

I grew up in Banyuwangi, a coastal district often referred to as the ‘Sunrise of Java’ and renowned for its rich marine resources and strong fishing traditions. In my family, smoked fish, especially ray, was a household favourite and part of our...

View full profile

PROJECT LOCATION : Indonesia

Project details

Wedgefish Conservation: Critical Habitat Mapping and Conservation Strategies in Java Sea Waters

Key objective

As the first dedicated wedgefish conservation initiative in Tuban, our aim is to combine research, awareness and action.

Why is this important

Wedgefish are among the most threatened rays in the world and their populations in the Java Sea are declining due to heavy fishing pressure and bycatch. By identifying key habitats and working directly with fishing communities, this project will help protect these species, safeguard local ecosystems and create a foundation for sustainable fisheries in East Java.

Background

The wedgefish population in the Java Sea is declining sharply and is listed as Critically Endangered by the IUCN. In Tuban, East Java, fishing communities operate trawls, seine nets and bottom-set gears, in which wedgefish are frequently caught as bycatch. Despite their vulnerability, little is known about where these fish breed, feed and grow. This lack of knowledge makes it difficult to design effective protection measures. Preliminary monitoring from April 2024 to March 2025 revealed that wedgefish in Tuban are dominated by three species: Rhynchobatus australiae, R. springeri and R. laevis, representing 46% of recorded rays. Most individuals landed were small to medium in size, indicating that many juveniles are being removed before reaching maturity. These findings suggest that the Java Sea, particularly the Tuban coast, may serve as an important nursery and spawning ground for wedgefish. This project responds to the urgent need to protect wedgefish by combining science, community engagement and policy advocacy. By mapping critical habitats, monitoring catch trends and promoting safe release practices, we aim to reduce mortality and provide evidence that will support stronger management. Beyond protecting wedgefish, the project will foster stewardship among fishers and raise community awareness, making it the first dedicated wedgefish conservation initiative in Tuban.

Aims & objectives

The overall objective is to aid the recovery of wedgefish populations in the Java Sea while supporting fishing communities. We aim:

To provide evidence for better management by mapping critical habitats.
To reduce wedgefish mortality by persuading fishers to voluntarily release juveniles and breeding individuals.
To build community awareness so that wedgefish conservation becomes locally recognised in Tuban.
To promote behaviour change and stewardship by providing training for fishers in safe release practices and encouraging them to participate in monitoring wedgefish.
To strengthen livelihoods in the long term by aligning fisheries practices with sustainable management.

You might be interested by these projects

Decoding Mexico’s orca ecotypes

By Jesus Erick Higuera Rivas

There is much still to be learnt about orcas in the Gulf of California. And since 2018, the Orcas Mexico project has been observing flexible and specialised feeding strategies, movement across the Eastern Tropical Pacific and patterns that suggest connectivity between the Gulf and populations in the Pacific. Jesus wants to determine if there is a previously undescribed orca ecotype in the Gulf of California. He’ll be analysing skin and blubber biopsies to understand their diet and reviewing acoustic and photo-identification data to decode their communication, gaining glimpses into their kinship and social structure. His project will help to inform effective conservation and management strategies.

Restoring sharks and reef resilience in Mnemba Island Marine Conservation Area

By Camilla Floros

Mnemba is one of Zanzibar’s most heavily used marine areas. The Mnemba Island Marine Conservation Area was declared in 1988, but for much of its history the area has lacked effective implementation, enforcement and science-based management. As a result, sustained fishing pressure and unregulated tourism led to widespread coral reef degradation and the near-complete loss of sharks and other large reef predators that once maintained ecosystem balance. Camilla is expanding the use of baited remote underwater video systems (BRUVs) to guide the establishment of fishery replenishment zones where ecological recovery will be encouraged by reducing fishing and tourism pressure in areas to increase fish abundance and improve reef condition.

Saving Seret’s butterfly ray

By Kehinde Adelakun

In Badagry in Nigeria’s Lagos State, fishing sustains coastal communities. Fishers bring in rays and small sharks daily, but there is no monitoring system, no guidance on safe handling and little awareness of which species are threatened. Living in shallow waters, sandy bays and estuaries, Seret’s butterfly ray slips under the conservation radar. Although rarely targeted directly, it is often caught accidentally in gill nets and trawls. Kehinde is combining science with local knowledge to monitor catches, map critical habitats and test safer fishing methods to protect this ray and the livelihoods that depend on healthy seas.

See all projects