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  • Overview
  • Objectives
  • Skills you gain
  • Costs to Consider
  • Site Conditions

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Mediterranean terrestrial biodiversity research experience
The Mediterranean biodiversity research is carried out in the valley of Krka National Park. At this site you will be working from dawn until late morning and then again in the late afternoon and evening helping a series of different research teams. During the heat of the midday period you will have a series of lectures about Balkans wildlife and conservation and help with data input and lab-work using samples sourced from the field. The projects include standardised transect surveys through a series of different habitats for butterflies (Pollard surveys), herpetofauna (standard search transects), birds (point counts), mammals (standard search transects for scat and spoor) and bats (acoustic surveys). In addition, there are standardised monitoring locations for bird and bat mist netting in a range of habitats and surveys to quantify the habitat at each of these standardised survey locations. On top of these standardised surveys designed to provide long-term data on the different faunal groups there are a series of investigations to describe population densities and ecology of groups such as moths (light trapping), grasshoppers, crickets and spiders (sweep netting), cave fauna (standard search transects and quadrats), fish communities throughout the valley (beach seining and trapping), nocturnal surveys of cat snakes (Telescopus fallax), Hermann’s tortoise (Testudo hermanni), Dalmation algyroides (Algyroides nigropunctatus) lizards, Beech Marten (Martes foina) and the effect of wolves on predator composition (camera trapping).

Adriatic marine training and research experience
For the marine research experience you will be based at on eof the marine camps being used ion Silba Island, Krk Island or at Pula. During this week if you are not dive trained you will complete a PADI Open Water dive training course. If you are already dive trained or would prefer to snorkel you can complete the Mediterranean ecology and survey techniques course, with two lectures and two practicals each day (either by diving or snorkelling). After completing this training you will be able to assist with some of the research surveys on Mediterranean fish communities, the recovery of the Noble Pen (Pinna nobilis) mollusc populations, the impact of sea urchin populations, seagrass and marine plastics.

Croatia Research Objectives

Krka National Park

The Krka Valley runs from the Dinaric mountains bordering Bosnia to the Adriatic and is only 77km in length. However, since the river runs through limestone there are some spectacular gorges and this is one of the most scenic river valleys in Europe. It is also important from a biodiversity viewpoint containing nine Croatian and three Krka endemic fish species and spectacular cave systems containing a number of potentially new species to science. Opwall together with Biota (a Croatian biodiversity research organisation) has built a research centre in the central part of the Krka valley with easy access to the whole park. The centre is based in a restored house and grounds within 100m of the park boundary and has access to all the habitats throughout the park and surrounding countryside. The National Park Authority have requested we perform baseline surveys to increase the known inventory for the Park, as well as collect long-term monitoring data to answer a series of their management questions.

Tourist visits to Krka National Park are heavily concentrated towards the lower stretches of the river and very few people visit the central and northern parts of the valley. The Biota/Opwall research centre is based within a rural community that has suffered from significant depopulation and land abandonment in recent years. The centre is designed to give benefits to the local community from the visits (e.g. provision of employment etc). Whilst the main research effort each year from this centre comes through the Opwall programme, the centre will remain open year round in an attempt to attract some of the many visitors to the Croatian coast further inland, increasing revenue for the Park and local communities.

Silba Island

Silba Island is in the northern Dalmatian archipelago and is a car and hotel free island. The island markets itself as a haven of tranquillity and much of the island is still covered by Mediterranean black oak and maquis. The objective for our partners on this island is to develop the first marine research centre for northern Dalmatia and they have a series of research projects on seagrass, sea urchins, protected species and fisheries, as well as marine plastics.

  • Attend lectures/workshops on biodiversity and conservation
  • Learn about the biogeography of the Dinaric karst and mountains
  • Explore unique cave flora and fauna
  • Learn many different survey methods for freshwater fish, birds, snakes and mammals
  • PADI Open water dive qualification
  • Participate in Adriatic ecology course
  • Help in estimating the health of sea grass
  • Help in establishing No-take zones for fishing
  • Learn to estimate population of endemic and endangered Nobel shell
  • Learn to adopt to team work and experience its importance
  • Immerse yourself in beauty of 2 national parks


The costs of a school group expedition can be highly variable. There is a standard fee paid to Opwall for all expeditions but the location you are flying from, the size of your group, and how you wish to pay all impact the overall cost.

You can choose to book the expedition as a package (which includes your international flights) or you can organise your travel yourself and just pay us for the expedition related elements.

If you are booking your expedition as a package, you also have the option of being invoiced as a group, or on an individual basis.

Croatia is hot during this time of the year! In both Krka and Silba the daytime temperature rarely drops below 30 degrees and can reach 40 degrees.

Fitness level required
Moderate. Whilst there are not many steep hikes in the forest, the hikes are still quite long and the temperature can make them tiring.

Creature comforts
At Krka we are in a renovated house in the countryside. You will sleep in dormitories with shared western style bathrooms and toilets, and in Silba it will be in dormitories, again with shared bathroom facilities. There is some limited phone signal in Krka (but not reliable for a data connection), but good phone signal in Silba.


  • Croatia
  • Krka National Park
  • Silba
  • Pag Island

Want to get involved with this project?


Want to get involved with this project?

Wallace House, Old Bolingbroke, Spilsby, Lincolnshire PE23 4EX, UK
| +44 (0) 1790 763194 | info@opwall.com