15 days old eel larva looking for food. Photo: Sune Riis Sørensen


Fish farming begins with stocking of fry, i.e. juvenile fish, and these can come from the wild or be produced on the farm. European eel is a targeted, high value species in fish aquaculture; however, production and markets for this species have been reduced due to a recent decline of the stock, leading to low abundance of juvenile glass eels that are used as fry in commercial eel aquaculture.

Captive breeding and larval rearing to the glass eels stage would overcome this obstacle for the industry; however, eels do not reproduce naturally in captivity due to complex hormonal control mechanisms that relate to their long migration to native spawning areas in the Sargasso Sea. Yet, such maturational barriers can be overcome through hormonally assisted reproduction and modern biotechnology, securing viable offspring.

Another challenge is to establish hatchery techniques and technology that sustains development and ongrowing of the distinct leptocephalus larvae, unique to the Elopomorph superorder that comprises European eel. Within this regard, larval longevity achieved by assisted reproduction and improved hatchery techniques, has been significantly extended in recent years, attaining large-scale egg batches that survival to the end of the yolk-sac stage, i.e. ~12 days post-hatch and beyond.

This progress now allows studies and measurements of key larval performance traits, thereby providing unique information on critical early life stages.  


The overall vision of this consortium is to establish breeding and hatchery technology for future commercial production of glass eels, leading to sustainable and profitable eel aquaculture. In this context, EEL-HATCH will enhance existing technology to breed European eel and raise larvae to the glass eel stage, thereby closing the lifecycle in captivity.

At present, eel farming relies exclusively on wild-caught glass eels and there is an ever-increasing demand for a captive-based fry production for sustainable aquaculture of this endangered species. Thus, captive breeding and hatchery technology will generate a new commercial activity that ultimately can re-establish the highly profitable eel market for the Danish and European aquaculture industry, including suppliers of fish feed and aquaculture systems, as well as retail supply chains, thereby adding value to the sector and society.


The EEL-HATCH consortium has seven partners and is lead by Technical University of Denmark.
Learn more about the EEL-HATCH partners


The EEL-HATCH project is funded by Innovation Fund Denmark.
Learn more about the Innovation Fund Denmark

Project period 

The EEL-HATCH project period is from 1 April 2014 till 30 September 2017.



1 MARCH 2024