Study 1 Effects of Habitat Alteration on the Abundance and Diversity of Pterygota at Cloudbridge Nature Reserve in Costa Rica by Anonymous  Abstract. This
study sampled Pterygota (winged insects) attracted to a ripe fruit bait
in three habitat types (primary cloud forest, forestry plantation and
former cattle pasture) in order to investigate the effects of habitat
alteration. The study, conducted during Costa Rica's wet season, tested
the hypotheses that diversity of insect groups would decline with
increasing habitat alteration (H1) and that insect abundance would vary
between habitat types (H2). 7 samples were taken from 3 sites in each
habitat type, using traps baited with ripe banana and a sugar/water
solution. Diptera were the most frequently collected insect group and
were far more abundant in the primary forest than the other habitat
types. A relationship between numbers of Diptera collected and rainfall
was also noted. Hymenoptera were most frequently collected from the
pasture, and least so from the forest. The greatest number of
Hymenopteran species was also recorded from the pasture and was lowest
in the forest. Coleoptera were most frequently collected in the pasture
and least in the forest. H1 was not supported. H2 was supported in
varying degrees depending on the habitat type and insect group
considered. Contributing factors are suggested for the observed
patterns of variation and the results are discussed in the light of the
available comparative literature and with respect to potential
ecological impacts. The full report: habitat_alteration_and_pterigota.pdf Data in an Excel file: habitat_alteration_and_pterigota.xls Study 2 Effects of Habitat Alteration and Seasonality on the Abundance and Diversity of Pterygota at Cloudbridge Nature Reserve in Costa Rica by Alison Brown  Abstract. This
study reports on data collected in early 2006 to follow up a previous
author’s 2005 pterygota study. The goal was to compare abundance and
diversity of winged insects across the dry and
wet seasons in a Costa Rican cloud forest. To compare habitat
variation, 8 sample sets were taken from three different habitat types:
primary forest, 3-year old plantation and recently deserted cow
pasture. The insects were collected in traps baited with ripe banana
and sugar water.
Traps in the primary forest recovered the most insects while those in
the plantation recovered the least. When the dry season data were
compared
to those of the wet, there was a striking variation in the abundance of
primary forest insects, especially Diptera. Other orders did not show
such variation, nor did the other habitat types. Habitat alteration
seems to have important effects upon insect abundance and diversity;
the 3-year old reforestation effort does not yet diminish these changes.The full report: habitat_alteration_seasonality_and_pterigota.pdf Data in an Excel file: habitat_alteration_seasonality_and_pterigota.xls Reseachers must bring independent funding for their projects, including travel and living expenses. Send us some information about your research qualifications, what you wish to study, and when you can come. If your project is accepted, we'll assist in finding accommodation and provide access to the reserve. We'll also publish the results of the research on the Cloudbridge website. To discuss your ideas, contact Ian & Genevieve Giddy (see the contact page). |
