June 2021 - Bats helping us restore pastures @MPNR
When someone thinks of bats, usually blood-feeding vampires come to mind. Yet most bats feed on insect prey and there are some that hunt for frogs and fish. Also, some bats pollinate flowers and there are those that feed on fruits. The latter are helping us restore pastures @MPNR.
©Guyana Conservation Network
Restoring pasturelands with native tree species has become an important activity at the Mesenia-Paramillo nature reserve. With more than 600 plant species identified in a one-hectare (2.2 acres) permanent plot set by Universidad de Antioquia under the directive of the Von Humboldt Institute at 2,400 meters (7,900 ft) elevation, a significant number of tree and bush species can be selected. Therefore, our park rangers with the help of other local stakeholders have been setting tree nurseries around pastures to be restored; each with a 10,000 seed/seedling capacity.
Since 2008 when the first plot to begin the MPNR was acquired, several areas of pastureland have been self-restoring. In most of the plots, the main pioneer species are Glory Trees (Tibouchina lepidota). Recently near the main station, we noticed that another tree species, known in the area as “Carate” (Vismia baccifera subsp. ferruginea) was becoming also a pioneer species. Interestingly, the main seed disperser for this tree species are bats. Coincidentally, our hummingbird feeders at the station were being visited at night by bats. Apparently, having the bats visit the feeders also caused them to disperse the “Carate” seeds near the station where these trees have flourished.
Additionally, our park rangers started noticing that several trees of a species known as “Barcino” (Calophyllum Brasiliense) were starting to fruit. This tree species has been cut down extensively in the Andes due to the quality of its wood and it has become uncommon in the region.
During the months of March and April, the fruiting bodies are ripe and, rather than collecting the seeds directly from the trees, they are searched for in nearby trees. The reason for this, is that bats grab the fruits and fly to nearby perches where they feed on the outer crust exposing the inner seed. The seeds are then dropped to the ground where they can be collected.
Bats are saving us lots of time and work that would entail climbing to the very tall “Barcino” trees, taking the crust of the fruiting body, and loosing many seeds as they may not be at the correct ripe stage.
The seeds provided to us by bats now undergo a final cleaning and selection process and are buried in humid soil to begin the germination process.
Two weeks later, the seeds are ready to be bagged. One must be careful to place the seed in the correct position for the rooting system to develop.
We expect to collect some 100,000 seeds of “Barcino” and plant these tree species at the reserve and in other areas of the western Andes.
After one-month of being planted, a 90% germination and survival rate has been obtained at the tree nursery. By the end of July and early August, the "Barcino" trees will be ready to be planted. Such large trees will absorb important amounts of carbon from the atmosphere for years to come until they reach maturity.