The Las Cruces – Guaymí Biological Corridor in Southern Costa Rica
Coto Brus county (where Las Cruces is located) is one of the most deforested counties in Costa Rica; it is also one of the most recently deforested. The area is highly fragmented and the regional landscape is made up of a mosaic of mixed-use agricultural fields. Originally a principal coffee growing region, most agricultural land has been converted to pasture in the last decade due to the global drop in coffee prices. Given the steepness of land and high annual rainfall, conversion to pasture has resulted in severe environmental problems including soil erosion, water contamination, and flooding.
Las Cruces owns one of the largest remaining forest fragments in the region. With roughly 200 hectares (ha) of primary and ~50 ha of secondary forest, the fragment is incredibly diverse and home to over 2,000 plant species and over 100 mammal species including three on the World Conservation Union’s threatened and endangered list. However, at a little more than 325 ha, LCBS is effectively a forest island embedded in a pastoral landscape, and most fauna (and even flora) are either trapped within the boundaries of the station or are unable to reach it due to its isolation. Aside from continued environmental problems, this excessive fragmentation had led to a steady loss of biodiversity in Coto Brus, where at least 7 mammal species have gone locally extinct (Pacheco et al. 2006). Accordingly, it is increasingly urgent to address the critical state of habitat protection in the region and pursue a more proactive conservation agenda.
Composite image from the Hymap sensor flown by NASA in 2005. Outlined in white are the Las Cruces and Guaymí protected areas, that are ~7 km apart. Dark areas are forest, lighter areas have been cleared, and white patches are clouds.
Although a number of smaller fragments still persist, most of the land adjacent to LCBS is under pasture cultivation, and it is simply not an option to acquire forested land to augment protected areas. Instead a restoration-oriented approach is required and the pastures that surround the station need to be purchased and reverted to forest. Such an effort was undertaken previously when the 30 ha ‘Rojas’ property was added to Las Cruces in 1999, and the pasture quickly developed into a young secondary forest through natural seed dispersal, the planting of seedlings, and the active suppression of pasture grasses. The purchase of additional properties, which will be similarly restored, will create a biological corridor that links the larger fragments adjacent to Las Cruces with the much larger Guaymí indigenous reserve (7,500 ha), due west of the station (Figure 1). Ultimately, this corridor will provide access to additional habitat (both by creating ‘new’ habitat and by reconnecting forest fragments) and help stabilize isolated populations in the Las Cruces fragment as well as in the smaller proposed acquisitions.
The Las Cruces – Guaymí corridor spans 7 km and would ideally be at least 1 km wide. Using these dimensions, the corridor would incorporate roughly 1,200 ha once completed. A majority of these lands are forested and are sufficiently remote to not be under immediate threat. These areas (which encompass some ~700-800 ha and are closest to the Guaymí reserve) would be evaluated in a second corridor expansion phase to be negotiated after the completion of the first phase. For this campaign, we are focused on several properties directly west of the LCBS reserve that total 300-350 ha (Figure 2). Key properties of interest are the two larger properties (Romero & Gamboa) – which together total ~250 ha – as well as several smaller adjacent sections. These properties will consolidate a number of forest fragments in the immediate vicinity of Las Cruces, protecting over 150 ha of additional forested land while adding ~150-200 ha of land in need of restoration. A ~1.5 ha natural lagoon also falls within the proposed acquisition. A number of lagoons are found in the region and they are of historical importance with one lagoon in particular harboring the oldest known maize pollen record for southern Costa Rica (Clement and Horn 2001). The incorporation of a lagoon within LCBS will further increase both the research and ecotourism potential of the station.
Aerial image of LCBS (blue) showing details of corridor properties of interest to the west of the station that would represent Phase 1 of the project. The Guaymí reAreas in dark green are forested; lighter areas have been cleared.
Purchasing land in need of restoration is key to the overall strategic plan envisioned for Las Cruces. Few tropical biological stations are located in such a human-altered landscape, and it is this setting that makes Las Cruces an ideal and almost unique location to examine the effects of fragmentation and isolation on plant and animal communities, in addition to research on biological corridors and restoration ecology. With a long history of habitat protection in Coto Brus, LCBS has developed a strong reputation for its conservation achievements, both at the regional level and at the national and international stage.
Accordingly, by embarking on an active land conservation and restoration campaign, the field station can further position itself as a leader in a research field of increasing global importance while simultaneously protecting threatened habitat. The timing is also critical - not only due to habitat loss, that is placing additional strain on the remaining fragments around Las Cruces, but also the recent dramatic rise in land values prompted by foreign retirees moving to the area. The good news is that we have started! In late 2008, we made a first purchase, adding ~25-ha of mostly former pastureland to the LCBS protected area, and in 2009 we added a further 39-ha. This represents an increase of more than 20% in the area protected by Las Cruces and is an important first step towards achievement of this ambitious project. But there is still much more that needs to be done!
Please consider making a donation to this important cause and help protect and restore an incredible biodiversity hotspot in southern Costa Rica. Land value in the region fluctuates considerably but we anticipate paying somewhere in the range of $4,000- 6,000/ha. To date we have raised more than $200,000 since the campaign started in late 2006, but we have a long way to go! Any gift is welcome.
To make a donation, please fill out and send in a donation card ( 1.28 Mb ) along with your check or credit card information. On the donation form, make sure you mark the land campaign box. For further information on the campaign please contact the station director:
Dr. Zak Zahawi, Director Las Cruces Biological Station & Wilson Botanical Garden Organization for Tropical Studies Apdo 73-8257 San Vito de Coto Brus, Costa Rica
Literature Cited: Clement, R. M. and S. P. Horn. 2001. Pre-Columbian land-use history in Costa Rica: a 3000-year record of forest clearance, agriculture and fires from Laguna Zoncho. The Holocene 11:419-426.
Pacheco, J., G. Ceballos, G. C. Daily, P. R. Ehrlich, G. Suzán, B. Rodríguez-Herrera, and E. Marcé. 2006. Diversidad, historia natural y conservación de los mamíferos de San Vito de Coto Brus, Costa Rica. Revista de Biología Tropical 54:219-240.