Encyclopedia EcoRaft
What are Heliconia? What do Erythrina do for the ecosystem? How does an island become deforested? This page has the answers to these ecology questions and more. Click on images to see a bigger view.
You can see pictures of the restoration team at work in Costa Rica in our Restoration Gallery.
Who's Who in EcoRaft?
Coral Tree (Scientific name: Erythrina berteroana)
The Coral tree is easily recognized by its stunning canopy of red
flowers that attract hummingbirds and other pollinators. As an early
successional species, the Coral Tree grows well in the intense sunlight
of open pasture. As the tree grows, it casts shade, creating a more
hospitable environment for neighboring seedlings. The roots of the
Coral Tree also host bacteria that "fix" (or produce) the important
nutrient nitrogen. The added nitrogen is not only used by the Coral
Tree but by neighboring plants as well , making it a valuable species
in restoration.
Heliconia Plant (Scientific name: Heliconia pogonantha)
Heliconia are a diverse group of plants often found in the understory
of tropical forests. They tend to grow best under the partial shade of
a tree or in small forest gaps. They are best recognized by their giant
leaves (4 ft!) and large colorful bracts (3 ft) that hold hundreds of
flowers. Heliconia in Costa Rica are almost always pollinated by
hummingbirds.
Tabebuia Tree (Scientific name: Tabebuia ochracea)
The Tabebuia Tree is a late successional species found throughout Costa
Rica. They can grow up to 90 feet tall! However, Tabebuia are best
known for their spectacular "mass blooms" where all trees in an area
flower together within a few days of each other. The yellow flowers
attract bees that carry pollen from one tree to the next. Unlike the
Coral Tree, Tabebuia seeds grow best under the shade of other plants.
In time, they will grow above the early successional trees and replace
them.
Centropogon vine (Scientific name: Centropogon granulosus)
As a vine, Centropogon relies on other plants for support. The vine begins its life in the shady understory, climbing steadily
upward until it reaches the full sun of the uppoer canopy. With its extremely long, curved tubular flowers, Centropogon is only
accessible to hummingbirds with similarly long, curved bills, such as the White-tipped Sicklebill.
Rufous-tailed Hummingbird (Scientific name: Amazilia tzacatl)
Rufous-tailed Hummingbirds are one of the most aggressive of the
territorial Costa Rican hummingbirds. Although small even for a
hummingbird (4 in.; 5.2 g), the Rufous-tailed frequently chases larger
birds away from its precious flowers. You can find this species in open
habitats and along forest edges.
Long-billed Starthroat (Scientific name: Heliomaster longirostris)
As the name suggests, the Long-billed Starthroat has a long, straight
bill for feeding on the nectar of long tubular flowers, like those of
the Coral Tree. Like the Rufous-tailed Hummingbird, it defends small
patches of flowers against other hummingbirds. The bright red feathers
on the throat of a male Long-billed Starthroat shimmer under the right
angle of light. This flash of color is used to catch the eyes of
potential mates!
Violet Sabrewing (Scientific name: Camplyoterus hemileucurus)
This beautiful hummingbird is often found along forest edges and
understory, visiting flowers of Heliconia. Although a relatively large
hummingbird (11.5 g; 6 in.), the Violet Sabrewing does not usually
defend territories. Instead, it follows a "trap-line" of small flower
patches that it revisits several times throughout the day.
Green Hermit (Scientific name: Phaethornis guy)
Another understory, trap-line species is the Green Hermit (6 in.; 6 g).
It has a long, decurved bill for sipping nectar from Heliconia flowers.
Males congregate on leks of up to 20 individuals where they sing and
display to attract a female.
Deforestation and Restoration
What is ecological succession?
Environments are constantly changing. When changes occur, such as the availability of water, nutrients, and sunlight, the types of plant and animals that inhabit these environments can also change. Biologists call this process ecological succession. Ecological succession is the gradual change in the kinds of plants, animals, and other organisms that live in an ecosystem as it ages with time. For convenience, succession is often broken down into three stages: early, middle, and late stage succession.
Plants and animals that live within the same stage of succession often share similarities with one another. For example, plants that inhabit early successional stages tend to grow rapidly, and do so under high light and low nutrient availability. In contrast, late successional plant species grow slowly and prefer shadier habitats.
One of the goals of EcoRaft is to present these patterns and illustrate how they can be used to improve restoration. One important pattern is that degraded environments tend to look a lot like environments in early successional stage. Introducing species that naturally grow well in early succession may therefore grow well in degraded environments, providing a jump start to restoration. Middle and late successional species can then move in, hastening what is usually a very slow process.
What is ecological restoration?
Ecological restoration is the field of science concerned with understanding degraded environments and discovering ways of returning them to their original state. Tropical ecosystems can become degraded many ways, including by logging and intensive farming. When the land can no longer support these activities, it is often abandoned. Tropical ecosystems are particularly vulnerable to this process because of their nutrient poor soils and the heavy rainfall that quickly washes away the thin top soil. Unfortunately, forests may not grow back to their original state without human assistance. The goal of restoration ecologists is to find ways to initiate or speed up this recovery process. Your goal as an EcoRaft user is to restore the rainforests of several tropical islands. Just like in nature, the fate of your EcoRaft ecosystem will depend on how you choose to take care of it.
Why is ecological restoration important?
Ecological restoration is important for many reasons. Ecological restoration re-establishes the interactions between plants, animals and their environments. Restored ecosystems also provide food and shelter for wildlife. They also offer valuable services to people including clean water, protection from natural disasters like floods and landslides, and place for recreation and rejuvenation.
Advice to the young restoration biologist
One of the most important parts to being a good biologist is to carefully observe your surroundings. What do you see, smell, and hear around you? For example, do you see or hear animals? Do the flowers have a pleasant scent? What shape are they? These are the kinds of questions biologists ask themselves when exploring the natural world. You will need to use your own power of observation to understand and restore the EcoRaft ecosystem.
For more information about restoration ecology, please visit Lynn Carpenter's web site.
Last updated: September 1, 2005