Abstract Detail

Charles Heiser Special Contributed Paper Session

Theiss, Kathryn [1], Holsinger, Kent [2].

The impacts of harvest on a rare Malagasy orchid.

Humans primarily harvest plants for food, shelter and medicine. However, some plants are valued solely for their beauty. We have focused on the harvest of the extremely rare Malagasy orchid, Erasanthe henrici, whose only known use is in horticulture. This species is restricted to isolated, highly fragmented forest patches and suffers from low fruit set. In some populations, fruit set is almost non-existent. In addition, some populations are depleted by collection of plants for resale in the horticultural trade. We built demographic models for six populations based on field observations from 2007-2010 and projected the population sizes using these models 25, 50 and 100 years into the future. We then simulated varying levels of harvest (1, 3, or 5plants per year) in two ways: (1) choosing the plants to be harvested at random and (2) restricting the harvest to reproductive individuals. Populations declined under both harvest scenarios at any level of harvest, but the declines were most pronounced when harvest was restricted to reproductive plants. Since reproductive plants are more likely to be harvested, annual harvest of even a single plant is more than any of these populations can sustain.

Broader Impacts:

1 - University of Connecticut, Ecology & Evolutionary Biology, 75 N. Eagleville Road, U-3043, Storrs, CT, 06269-3043, USA
2 - University Of Connecticut, Department Of Ecology & Evolutionary Biology, 75 N. Eagleville Road, U-3043, STORRS, CT, 06269-3043, USA

Keywords:
Madagascar
Demography
Population viability
Orchid conservation
Sustainable harvest.

Presentation Type: Oral Paper:Papers for Topics
Session: 03
Location: Lindell D/Chase Park Plaza
Date: Monday, July 11th, 2011
Time: 10:30 AM
Number: 03011
Abstract ID:188