Presenter Information

James Lucas, Colby CollegeFollow

Location

Parker-Reed, SSWAC

Start Date

30-4-2015 9:00 AM

End Date

30-4-2015 10:55 AM

Project Type

Poster

Description

The sohisika (Schizolaena tampoketsana; family Sarcolaenaceae) is a little-known, highly threatened angiosperm endemic to the forest fragments and savanna of the Hauts Plateaux region at Ankafobe Commune, Madagascar. Through targeted surveillance of sohisika at Ankafobe, this study aimed primarily to characterize the demography of the sohisika via GPS mapping of latitude, longitude, and altitude, through dendrometric measures such as height and diameter at breast height (DBH), and through calculation of distribution patterns via Morisitas index. Secondary goals aimed to describe the ecology of the sohisika within its environment and hoped to identify patterns between age class, aspect, habitat, and surrounding vegetation. Total population was determined to be at least 1115, growing within an area of less than 50 square kilometers between 1400 and 1500 m above sea level. Most individuals were small shrubs (high) growing on savanna; however, individuals growing in forest fragments could grow to 18 m in height and 93 cm DBH. Using various diameter and height size thresholds, the mature population was estimated to be between 203 and 370, greater than the previous estimate of 160. Based on data obtained from this survey, the sohisika is hypothesized to survive in its disturbed, fragmented environment via dispersal between low-quality savanna and high-quality, transient gallery forest fragments and is thus a potential model organism for metapopulation studies. In addition, this research provides sufficient supplemental demographic information to place the sohisika on the IUCN Red List as CR Critically Endangered.

Sponsoring Department

Colby College. Biology Dept.

CLAS Field of Study

Natural Sciences

Event Website

http://www.colby.edu/clas

ID

938

Included in

Biology Commons

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Apr 30th, 9:00 AM Apr 30th, 10:55 AM

Demographic Survey of the Sohisika (Schizolaena tampoketsana)

Parker-Reed, SSWAC

The sohisika (Schizolaena tampoketsana; family Sarcolaenaceae) is a little-known, highly threatened angiosperm endemic to the forest fragments and savanna of the Hauts Plateaux region at Ankafobe Commune, Madagascar. Through targeted surveillance of sohisika at Ankafobe, this study aimed primarily to characterize the demography of the sohisika via GPS mapping of latitude, longitude, and altitude, through dendrometric measures such as height and diameter at breast height (DBH), and through calculation of distribution patterns via Morisitas index. Secondary goals aimed to describe the ecology of the sohisika within its environment and hoped to identify patterns between age class, aspect, habitat, and surrounding vegetation. Total population was determined to be at least 1115, growing within an area of less than 50 square kilometers between 1400 and 1500 m above sea level. Most individuals were small shrubs (high) growing on savanna; however, individuals growing in forest fragments could grow to 18 m in height and 93 cm DBH. Using various diameter and height size thresholds, the mature population was estimated to be between 203 and 370, greater than the previous estimate of 160. Based on data obtained from this survey, the sohisika is hypothesized to survive in its disturbed, fragmented environment via dispersal between low-quality savanna and high-quality, transient gallery forest fragments and is thus a potential model organism for metapopulation studies. In addition, this research provides sufficient supplemental demographic information to place the sohisika on the IUCN Red List as CR Critically Endangered.

https://digitalcommons.colby.edu/clas/2015/program/96