Disturbance

Disturbance by sheep and cows can be perceived in the grass and shrub páramo on the west slope of the Cocuy Range. Overgrazing results in the disappearance of the bunchgrasses of the grasspáramo. The Calamagrostis grass bunches have gradually been replaced by the overall spreading of a prickly ground-covering minigrass, Aciachne acicularis, from sites where it once has been established. Remnant stem rosettes survive and also ground rosettes like species of Hypochaeris, Acaulimalva , Senecio rhizocephalus, Geranium sibbaldioides ssp. elongatum and the cover of herbs like Orthrosanthus chimboracensis, Rumex acetosella, and Acaena cylindristachya increases.

Vegetation structure has changed completely with the arrival of ground-covering Aciachne acicularis. The fate of the remaining stem rosettes is also not encouraging: rejuvenation of Espeletiinae in these landscapes fails largely and it can be expected that they will entirely disappear under continued grazing from this sector of the Cocuy National Park together with the natural associated herbaceous species.

At this moment we do not know precisely how to restore these grazed landscapes and it seems they will remain long time in this condition, also because the establishment of bunch grasses is prevented by the thick mat of low prickly grasses which sometimes behaves as cushion grasses (Cleef 1979). The same happened in the shrub páramo, which is also largely destroyed on the west slope and difficult to study properly with so many open patches, mainly with Aciachne acicularis, Agrostis breviculmis and bunches of Orthrosanthus chimboracensis. In addition, the uppermost contiguous forest remnants are also half open because of long time grazing. In this context the new rule recently adopted by the Park and which forbids cattle grazing, is a very important one. We are of the opinion that this will be most favourable for restoration of the wildlife in the Park and will enable the return of a range of animals. The páramo vegetation will need more time to restore and Aciachne grass mat is likely to persist for some time. This makes germination and establishment of natural species difficult.

According to Notestein & King (1932) grazing by sheep is taking place since the Spanish Conquest and has since markedly changed the aspect and composition of the natural páramo vegetation. Last century it was estimated that there have been over 5,000 sheep roaming on the west side of the Cocuy Range (Mr. Joaquín Valderrama, 1973 pers. comm. to Cleef). Cows also entered páramos here in last century. Their effect on the páramo vegetation is different: specific grazing fresh grasses rich in nutrients, and also dunging and trampling around, mostly in level areas. During the time when extensive natural bunch grass stands existed fire must have been an important management tool that triggered young and fresh grasses for the cattle. In general the effect of burning in the uppermost grass páramo is limited because of the bedrock.

With people around since long ago also the construction of open water works, a man-made channel in the Lagunillas valley and along the Ritacuba slopes has been realized. Water runs gradually downslope to fincas (local farms) and the small towns of Cocuy and Güicán. Similar old aqueducts also exist in Ecuador and Peru. They conduct fresh water quickly downslope and this water is no longer functional in the maintenance of the páramo landscape.

The introduction of trout in the last century in number of glacial lakes up to 4200 m has changed the natural food chain completely. At least in 1972 all lakes of Valle Lagunillas and Laguna La Plaza were containing trout, but when these introductions were carried out is unknown to us.

The FARC guerrillas have had a longstanding presence in the region. Noteworthy, they murdered the director of the National Park , and for some years they controlled the towns of El Cocuy and Güicán and some villages downslope. They hunted wild animals, used fuel wood from the subalpine forests and forest and shrubby stands in páramo and have set fire in grass páramo and even houses, especially the National Park refuge in Lagunillas and elsewhere. Since about 2003 the army kicked the guerrilla out and the presence of the State has been restored. Bullets still could be found at Cusirí Pass, where the army forced them to leave for downslope to Arauca.

Recently in 2014 also an attack by ELN guerrillas on a Colombian Army unit took place; several soldiers and guerrillas lost their lives.

A relatively new threat to the area, since the guerrilla was ousted, is tourism. Moreover, melting of the lower part of the ice sheet has exposed areas that until recently were covered by snow and ice. Many adventurous trekkers now spend holidays in the area of the Cocuy Range, an activity that severely impacts  the lower humid superpáramo. Rubbish, damage or extraction of the scarce shrubs for fuel wood, and human excrements are found all around the camping sites as seen on February 11–12, 2012. Because of repeated complaints by the U’wa tribes the trekking around the Cocuy massif has been forbidden by the Park authorities in 2014.

Also potato fields have been present in Valle Lagunillas; we saw them still in 1977. Today they have disappeared and on most places natural high Andean forest succession is presently fully operational. The old farm houses with walls of boulders and adobe or stems of Espeletia lopezii and roofs thatched with bunches of Calamagrostis have almost disappeared today, but some of them still have been observed elsewhere in the Cocuy area.