Outside the little city of Otočac, Croatia, you can find The Croatian Centre for Indigenous Species of Fish and Crawfish in Karstic Waters. In a picturesque valley in a small, unassuming cottage next to a set of clear ponds, the Centre conducts research for the conservation of native populations of fish and crayfish. 


At the Croatian Centre for Indigenous Species of Fish and Crawfish,
water runways for raising native trout species. 

The Centre focuses on breeding and restocking vulnerable native species of trout and crayfish, which face several threats, including the introduction of invasive species. An invasion occurs when a species is introduced to a new area, and it spreads and causes harm to the native species and habitats (to learn more, see my previous blog).

One native species under threat is the noble crayfish. These crayfish, also known as European crayfish or Astacus astacus, are globally listed as vulnerable due to the effects of invasion and disease. These crayfish are economically and culturally important as a food source, and ecologically as prey for other species. Unfortunately, a 2013 study indicated a 36% decline among native noble crayfish populations. To combat population decline, the Centre is developing new techniques for captive breeding to bolster population abundance. Captive bred noble crayfish will be released into the wild to restock natural waters.  


Juvenile noble crayfish, native to Europe, grow in bins at the hatchery. Populations of this crayfish have been largely displaced by invasive North American species. 

The FINS Conference group toured the hatchery, where breeding efforts are undertaken to
combat the decline in native species.

I traveled to Croatia this past summer to attend FINS, the “Freshwater Invasives – Networking for Strategy” Conference. The field trip to the breeding center for native species was fun and fascinating, but my real purpose was to participate in conference discussions and to get input on a project for my last Masters internship. It was my job to identify opportunities for a new program to protect endangered freshwater species by eradicating the invasives that threaten them. Why freshwater invasives? Freshwaters are disproportionately biodiverse and highly threatened by invasions. Freshwater habitats are also relatively small and isolated (in contrast to continental or oceanic areas) which makes them easier to treat. 

At FINS, European experts on invasive species came together to exchange research findings and discuss how we can improve action on this major threat to biodiversity. It’s more than just talk – these meetings are productive: the first FINS Conference in 2013 led to the publication of an important article detailing the top 20 issues for managing invasive species in Europe. 


On the main square in Zagreb, Croatia: leading the charge against invasive species!​

The Opera House at sunset. 

This year, I joined the other attendees in evaluating progress on these issues and producing a new invasive species management report (in review). One of the biggest improvements in invasive species management is the plan introduced by the European Union, which mandates that all member states implement measures for prevention, early detection, rapid eradication and management of invasive species of concern. Meanwhile, in the US, President Obama added new considerations for invasive species management just last month.        

At the conference in Zagreb, I also participated in a workshop on data management. We discussed organizing and standardizing data on species and management methods. Not only is the type of data important, but also where it is located – and I have personally experienced the difficulty of conducting research when there is no centralized source of information. To this end, one group has conceived of a supernetwork called INVASIVESNET to link scattered datasets and working groups. This, in turn, will help managers around the world collaborate, learn from one another, and share successful techniques, leading to improved and integrated management. 


In Zagreb, I stumbled upon some aquatically-themed street art.

Despite improvements, many hurdles remain, such as insufficient funding, and lack of education and awareness. If people don’t know the dangers of transporting species, they may inadvertently cause invasions – and that is why it’s important for you to get informed! Learn what you can do to prevent invasions here.

Fortunately, by bringing experts and decision makers together, conferences like FINS are helping to protect biodiversity by improving prevention and control of species invasions.   


I give this conference two fins up!

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