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Annemarieke Spitzen, RAVON (Reptile, Amphibian and Fish Conservation the Netherlands)

When was the organisation founded?

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What is your position or role in the organisation?

I am project leader, and currently working on amphibian diseases (chytridiomycosis and ranavirus). Besides that I also participate in projects on the effects of landscape fragmentation, and I am part of the communication team.

What are the main goals of your organisation?

The aim of RAVON is to increase the number of sustainable populations of amphibians, reptiles and fish in the Netherlands.
 

Could you tell us something about recent projects?

The fire salamander

The fire salamander (Salamandra salamandra terrestris) has declined significantly due to the novel pathogen Batrachochytrium salamandrivorans (Bs). This ‘chytrid 2.0’ has caused the population to decline with 96%. We are working to safeguard this species, and we simultaneously study the devastating effects of Bs on amphibian populations.

The fire salamander is a sturdy black and yellow terrestrial salamander. Adult specimens measure approximately 16 centimetre, and the animals can be found active throughout the year. The females deposit their larvae in spring in the brooks in deciduous forests on hillsides. The species lives in the Netherlands at the very edge of their distribution range and in this region it is confined to the old growth stages of this forest type.

For a long period of time, we considered the species to be stable, but from 2008 onwards dead fire salamanders were found. From 2010 onwards an extremely sharp decline in the number of sightings of living salamanders was noticed. Thanks to dedicated volunteers this decline was noticed and recorded. Considering the period 1997-2012 the species showed a very strong and significant decrease in all populations, and over this time frame the total population decreased by 96%.

Common spadefoot

The future looks pretty grim for the common spadefoot (Pelobates fuscus) in the Netherlands. The species may disappear in the near future when no immediate action is taken. We therefore started a ‘rescue-plan’ to protect and conserve this species.

The common spadefoot is a small stubby toad, with remarkable eyes that slightly stick out of their heads. On their backs they have an arrow shaped pattern. The species is listed as ‘threatened’ on the national Red List. The amount of suitable terrestrial and aquatic habitat for this species decreased significantly over time, and because of this the dutch government started a Species Action Plan. Despite the fact that during a ten-year period a lot of time and energy has been spent on habitat restoration, the smallest populations did not respond, and suffered most likely from inbreeding depression. Therefore we started a breeding and restocking  and reintroduction project to safeguard the species for the future.  We yearly collect egg strings and we are raising them in nurseries to increase the hatching  success, and give the larvae a headstart.  The larvae are then released to their natural environment.

Batrachochytrium dendrobatidis

The fungus Batrachochytrium dendrobatidis (Bd) is the causative agent of chytridiomycosis. This disease has caused many species of amphibians to decline significantly, or even go extinct. In the Netherlands we study Bd since 2009, and we have found that the fungus is omnipresent, but – up till now – we have not detected any mass mortality events attributable to Bd. Nonetheless, we know that we currently balance on a delicate scale and that the environmental conditions, the host species or the pathogen may alter in such a way that amphibians do become susceptible to the disease.

What is in your opinion the biggest success of your organisation since it started?

I regard our involvement of the discovery of the novel pathogen Batrachochytrium salamandrivorans in close collaboration with a large team of scientists one of our biggest successes. Besides this, I also take big pride in our ability to bring so many people together who are passionate on either one of the species groups and collectively work on their conservation at several levels, from the practical field work, via monitoring to lobbying at government level.

Do you have any specific goals in the near future?

For me personally,  yes. I would very much like to finish my doctorate thesis in due time.

Why is your work so important ?

My work, and RAVON’s work in particular, is immensely important because we collectively work on the conservation of species that are being threatened in their existence and may not unconditionally count on the sympathy of  people.

Could you give an idea, what organisations like the Herpetofauna foundation, can contribute to your work?

Herpetofauna is capable of spreading the word of all the work that needs to be done, and Herpetofauna can bring people together in their aim to help in the conservation of reptiles and amphibians worldwide. By their educational projects they can reach out to many people, and generate funds that can be attributed to a great diversity of projects.

How can people get involved in your work?

People can participate in our work on various levels. They can join by participating in excursions that are freely accessible, or they can start monitoring a transect for the Network Ecological Monitoring. Each year in November we have a symposium covering a wide range of topics, which provides ample opportunity to meet people.  Our website provides you with all the information www.ravon.nl