As a result of seasonal variation in rainfall in the Andean headwaters, the rivers of the Amazon basin are subject to large fluctuations in water levels throughout the year that flood the surrounding forest. The Pacaya-Samiria National Reserve is no exception, with as little as 2% of land in the reserve above water at the height of the flooded season. The forests of the Pacaya-Samiria flood as the waters rise between December and June, the onset of rainfall coincides with high fruit production that is, the primary dietary component of a wide number of primate species. In recent years these normal seasonal changes in rainfall patterns have become more intense, which has been tentatively attributed to climate change. Consequently, dry and rainy seasons are more pronounced resulting in unpredictable food supply and the extent to which primate populations can adapt to these changes is not yet known. Investigation of the impact of changing rainfall patterns on the abundance, diversity and distribution of primates in the reserve will involve line transect surveys across forest types that flood to varying degrees with distance sampling to calculate density of primate species. These data may be added to the long-term datasets to investigate changes to primate abundance over time in relation to water levels. Forest structure and fruit availability data may be collected from a series of habitat plots spaced equidistantly along each transect. Each primate encounter can then be linked to the nearest habitat plot along the transect providing a corresponding set of habitat variables for primate record. From this, habitat preferences of each species may be calculated and the habitat variables affecting primate abundance and diversity at each plot can also be investigated.
The Amazonian forests of Loreto, Peru are situated in the western Amazon basin and harbour some of the greatest mammalian, avian, floral and fish diversity on Earth. Operation Wallacea is joining a series of projects in this area that have been running since 1984 organised by FundAmazonia and various conservation groups, universities and government agencies. The vision of these projects is to set up long-term biodiversity conservation using a combination of community-based and protected area strategies. The research and conservation activities use an interdisciplinary approach to find a balance between the needs of the indigenous people and the conservation of the animals and plants.
The project is based in the 50,000 km2 Samiria-Yavari landscape as defined by the Wildlife Conservation Society and includes the Pacaya-Samiria National Reserve, the Yarapa river, theTamshiyacu-Tahuayo Community Reserve, the Yavari-Miri river and the Lago Preto Conservation Concession – see https://peru.wcs.org/en-us/Wild-Places/Mara%C3%B1%C3%B3n-Ucayali.aspx.
Our partners are working in all these areas and are establishing long term data sets on annual changes in key taxa from the Pacaya-Samiria reserve, Tamshiyacu-Tahuayo Community Reserve and the Lago Preto Concession. In 2019 our partners would like the Opwall teams to establish a new long term data set but this time concentrating on the Yarapa river site, and will continue with the annual monitoring in previous locations. As a result of this development, long term biodiversity data from 4 separate varzea and terra firma areas across the landscape will be available to compare how biodiversity is changing across the whole region.
The Yarapa study site will be on the landmass that connects the Pacaya-Samiria National Reserve and the Tamshiyacu-Tahuayo Community Reserve. These two protected areas almost touch each other, and the flooded forest habitat at the Yarapa site consists of varzea habitat with riverine, open understory, levee, liana, palm swamp and tree falls. These are high nutrient ecosystems with heavy sediment water flowing through the understory during the high-water season.
The flooded forests (várzea) of this landscape are particularly susceptible to global climate change which appears to be increasing the frequency of extreme flooding events and low water periods. During the height of the annual floods, much of the varzea area is flooded, but this can be as high as 98% in extreme flooding events, confining land-based mammals (agouti, deer, peccaries, armadillos and tapir) to small areas of land and thereby significantly impacting their population levels. In times of extreme low water, fish populations and their associated predators (dolphins, river birds and caimans) are under stress. The datasets managed by Fund Amazonia for this landscape, which is based on the annual surveys completed by the Opwall teams and others, are the most extensive in any of the Peruvian reserves and is showing the impact of global climate change on a range of taxa and on the livelihoods of indigenous people. This information is being used to make management decisions for the reserves and policy decisions for conserving the Peruvian Amazon including hunting quotas for the indigenous communities (see https://fundamazonia.org/peccary-pelt-certification.html).
The temperature varies very little in the area where we are based in Peru. It averages between 25 and 35 degrees Celsius (70 and 90 Fahrenheit). The humidity will usually always be over 75%, which can make it feel quite hot and sticky. During the evenings, the temperature drops and it can feel much cooler but still usually stays around 20 degrees.
Fitness level required
Moderate. This project will be based in the forest, where terrain can be quite uneven and muddy, and where you may also need to cross small streams. You will spend the majority of your day in the forest in humid conditions, which can be quite physically tiring (but great fun!).
Facilities in Peru are on a research boat where you will sleep in bunk beds in a shared cabin. The bathroom is also shared and you can expect hand flushed toilets and cold showers. You will have no cell phone signal or wifi.