Osa Birder: Avian Habitats and Passive Reforestation
Liz Jones, Bosque del Río Tigre, info@osaaventures.com

 

 

Melastome Leaf

    What an honor to live on this peninsula with approximately 2.5% of the species found world-wide and be privy to such ecological diversity. We are given opportunities daily, to observe, first hand, the incredibly complex relationships and dependencies among various species. Until I moved to the Osa, it was never as clear to me how important one species can be to another, how various species have co-evolved.

    One of the more fascinating experiences, for me, has been observing my passive "reforestation project". No, I have not planted a single tree. (well, maybe a few here and there). Why haven't I? Possibly my ignorance about the forest caused me to hold off, or possibly my innate urge to let things be.

    I have been watching, for 7 years, various disturbed areas regenerate forest all by themselves. Luckily, I do have patches of fairly integral forest nearby and the greatly disturbed areas have been maturing quite well. I have learned an incredible amount about forest regeneration. I have learned the importance of the common pioneer species such as Balsas, Capolins, Cecropias, Pipers and Melastomes. I have seen that standing dead trees are almost as important as live ones.

    I often hear people talking about the forest species they are planting in hopes of having a mature forest in the future. But I rarely hear discussions about the seed dispersers, pollinators and the common pioneer species, which are so important to a healthy diverse forest. I'm not an expert but it seems to me that one should cultivate a healthy, diverse light-gap or successional forest first, if one wants to have a healthy mature forest in the future.

 

Cecropia

    I suppose that rule #1 should be to bring in the pollinators and seed dispersers. It may take awhile to get the larger mammals but the birds and bats are easy. While some species of bats and birds may be seed predators that destroy the seeds or drop them under the mother tree, others will disperse the seeds whole and viable. Follow the example of Mother Nature. The first trees to develop in a disturbed area are also the best trees for bringing in the birds. Someday sit down for several hours and observe how may species of birds visit a fruiting Cecropia or a flowering Balsa. I believe that just about any bird that does not mind heights can be found feeding on one of these two trees. Yesterday, I actually watched an Anhinga feeding on a Cecropia. That was a first for me. Guabas, Capulins and trees of the family Melastomataceae are also important bird attractions. Guaba, of the family Fabaceae, genus inga, are the large, fast growing trees with the long seed pods. They attract a lot of insects and, with the insects, the woodcreepers, flycatchers, warblers, gnatcatchers, trogons and the usual assortment of tanagers and relatives. When the Guabas are flowering, their crowns are full of hummingbirds. I can almost always find a White-crested Coquette in a newly flowering Guaba. Gallinazo, family Fabaceae/Caes.is a species that grows up to 12 ft a year and when mature is a favored perch for Toucans and during December, with a good scope, you will see numerous hummingbirds feeding on its beautiful yellow crown. There are 5 species that go by the common name Capulin. Four of these are in the family Tiliaceae. The Muntingia calabura, trichospermum galeotii, t. grewifolium and dicraspidia donnell-smithii. The latter two bloom in November, December and January. The other species is in the family Ulmaceae, trema integerrima. These trees are always full of small bird species. Melastomataceae is a huge family, prolific in light gaps. They produce fruits high in sugar and favored by the tanagers, manakins, euphonias and honeycreepers. The melastomes are the plants and trees, with the parallel veins that come together at the leaf tip, (there are some species lacking this feature that are more difficult to identify). I often see euphonias spending as much as a half hour in one tree feeding on the fruits.

Capulin

    Birds that like to stay low, favor Heliconiaceae (heliconia), Marantaceae (prayer plant), Costaceae (costus), all from the order Zingiberales and plants of the family Melastomataceae. The heliconia, and its relatives, are favored by almost all species of hummingbirds and the hermits use the heliconia for nesting. I've also seen manakins, Ochre-bellied Flycatchers, and the whole assortment of tanagers and garden birds visiting these plants. I suppose some birds are looking for the insects that are attracted to the nectar and others simply have a "sweet tooth".

    I have mentioned only a few of the easiest to identify and more common light-gap species. There are many more. All these species of plants enjoy sun and if they have not developed on their own, they are fairly easy to plant successfully. Next, if you already have a good number of these common pioneer species, you may want to consider providing shelter and nesting areas for all the visiting birds. Allow large areas to become overgrown. It's a natural part of a successional forest. These areas are especially important for the Riverside Wren, Black-bellied Wren, Great Antshrike, Northern Bentbill, (a type of flycatcher), Orange-collared Manakins, Olivaceous Piculet, Black-striped Sparrow, and the spine-tails. In addition to providing shelter, the underbrush will protect the soil and provide shade for some of the more light sensitive tree species. These overgrown areas are also attractive to many of the smaller mammals including agoutis, anteaters and armadillos. After several years you will notice the underbrush in these areas thinning out as the stronger tree and plant species create extreme shade. As this happens the deep forest species will start to move in. You'll see Black-faced Antthrushes, Marbled Wood-Quail, Black-cheeked Ant-Tanagers, Chestnut-backed Antbirds, forest falcons, Great Currasow and the tinamous.

    As time goes on, some of the early pioneer trees will die. Control your urge to clean and groom. These dead trees provide homes for woodpeckers, parrots, parakeets, toucans, aracaris, martins, woodcreepers and tityras as well as an excellent food source for insect feeders. As the nesting season gets into full swing, many birds will switch their diets to include more protein-rich insects, which are needed for fast development of the nestlings. It is also important to leave shorter stumps, which may provide a nesting site for several birds including the Black-faced Antthrush or the Black-throated Trogons. Once you have enough shade and moisture you will have termite nests. Numerous avian species will nest in these termitaries including the Slaty-tailed Trogon.

MARANTACEAE

    Another good rule; don't rake all the the leaves. The leaves not only provide homes for the insects, lizards and small frogs that will attract the Great Tinamou, Little Tinamou, Marbled Wood-Quail, Grey-necked Wood-Rail, Chestnut-backed Antbird and various ground doves, but they also provide the right conditions for germination of all those seeds your local birds and bats have planted.

    With the great bird habitat you've created, it won't be long before you start to notice seedlings appearing from many of the other secondary and mature forest species. Chilimates, Higerons and Matapolos, family Moraceae genus ficus, Cedro Amargo, (a relative of mahogany), Guacimo colorado, (Another Tiliaceae with a reddish-brown color to the underside of the leaf), Guacimo ternero(mammals love the fruit) Cristobal, Peina de Mico, Fruta Dorado, Ajoche colorado, Ceiba, Zapote, Zapatero, Sangrillo, Ajo, Golondrino and Baco, to name a few. You will also begin to notice various fruiting and flowering epiphytes appearing in the crowns of your trees. These are very attractive to the avifauna.

    At this point it may be a good time to stop bird watching for a few days, get out of passive reforestation mode, and think about planting some of the species that have not yet appeared. Some of these missing species may be wind or mammal dispersed, such as the Caratigre and Manglio, genus Aspidosperma, or are extremely rare such as the Ajo Negro, Anthodiscus chocoensis or Sangrillo Colorado, Paramachaerium gruberi

COSTUS

And then there is the problem created by the silly birds that have planted all the largest forest species right next to the house. I definitely advise moving them before they are too big to transplant and you find yourself asking permission from MINAE to cut them down.

Liz Jones is the co-owner of Bosque del Rio Tigre Lodge. You may write her at info@osaadventures.com.

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