MHCC instructor shares tales of tropical scenery

By Walter Shriner

MHCC biology instructor Walter Shriner is on sabbatical in Costa Rica. He left in January and has also traveled in Guatemala. Spanish immersion is the main focus of his trip, as he works closely with CASS students. Shriner is also studying rainforest ecology, especially birds, and the local culture.

April 17, 2006
Northeastern slopes of the Cordillera Tilarán
Costa Rica

Latitude 10 degrees N; Longitude 24 degrees W; Elevation 1600 m; Distance to the sea 50 km.
These are the locational facts that by themselves conjure colorful images to geographers and ecologists. Physical realities that establish the conditions that currently surround me and my family: Cool, clear nights, and mild days, despite proximity to the earth’s equatorial band. Moisture-laden air from Pacific or Caribbean rising, cooling and changing to cloud, and subsequently releasing its life-giving cargo as mist.
Combined these conditions lead, even during the Costa Rican dry season, to forest vegetation that is lush and alive.
The ecological stage is set by these climatic conditions, but the details of who and what exists here are set by chance and history. In the forests nearby exotic birds like toucans and trogons roam in search of fruits, nightingale thrush and antbirds snatch insects forced into flight by marauding army ants, and scintillant hummingbirds and blue-gray tanagers remove sweet fluids from the flowers of canopy trees. Around the old farmhouse we currently call home are birds adapted to open fields and forest edges. Their evolutionary origins are unknown to me, but their current behavior and appearance reveal their habits and lifestyle.
Yellow-faced grassquits flick and flitter in their incessant search for insects and seeds. Clay-colored colored robins resemble their North American cousins in every way but color.
Several species of hummingbird make their rapid dips in and out of colorful flowers on trees and shrub. The similarities and differences outside the windows of this and an Oregon mountain cabin reveal a rich history of climate change and evolution, speak of barriers to travel and periods in which those barriers disappeared. A rich story to be read and pondered, hypothesized and studied. A beautiful landscape to behold.

With a traveling eye on nature,
Wally