Abstract Detail

Systematics

Breslin, Peter [1].

Spatially explicit population viability analysis using species distribution modeling for an island endemic cactus species of Baja California Sur.

Spatially-explicit Population Viability Analysis using species distribution modeling for an island endemic cactus species in Baja California Sur Many threatened plant species occur in isolated, restricted ranges that are characterized by patches or clusters of individuals. Yet, there is a continuing gap in accurate extent of occurrence (EOO) mapping and area of occupancy (AOO) mapping for plant species thought to be rare. In addition to this basic mapping information, there is a lack of data regarding smaller scale patterns of clustering on the landscape and data-rich species distribution modeling for many of these threatened plants. For example, the 3-dimensional and map projected EOO and AOO, patch density patterns, within-patch population densities, and other essential geospatial data ar partially or entirely unknown for Baja California’s Cochemiea halei, an island endemic plant species in the Cactaceae. Yet this species was recently assessed by the IUCN as being threatened and having declining population numbers. Determining the possible causes and effects of both the patchy and fragmented distribution is crucial to understanding the threats faced by C. halei. The combination of incidence data and abiotic variables such as soil type, texture, slope aspect, slope angle and microclimate profiles will be used to construct species distribution models, both maximum entropy presence-only models and presence/absence generalized linear mixed models. These models illuminate current and historical dispersal, interaction effects limiting site occupation, possible effects of climate change on distribution, and spatial patterns of pollination and gene flow. Specifically in regard to edaphic factors, the study site of Islas Magdalena and Santa Margarita includes extensive areas of serpentine rock and derived aggregates. Serpentine soil is known to drive plant endemism along the California coast, but this phenomenon has not been studied in Baja California, nor in general for endemic cactus species.

1 - Arizona State University, School of Life Sciences, 427 East Tyler Mall, Tempe, AZ, 85281, USA

Keywords:
geospatial analysis
species distributions
Rare Plants
conservation
biogeography.

Presentation Type: Oral Paper
Session: 37, Systematics II: Caryophyllids & Basal Asterids
Location: Sundance 4/Omni Hotel
Date: Wednesday, June 28th, 2017
Time: 10:15 AM
Number: 37001
Abstract ID:294
Candidate for Awards:None