Next Article in Journal
Next Article in Special Issue
Previous Article in Journal
Previous Article in Special Issue
Biology 2012, 1(3), 736-765; doi:10.3390/biology1030736
Article

Will Climate Change, Genetic and Demographic Variation or Rat Predation Pose the Greatest Risk for Persistence of an Altitudinally Distributed Island Endemic?

1
, 2
, 3
, 4
 and 1,*
Received: 3 September 2012; in revised form: 29 October 2012 / Accepted: 16 November 2012 / Published: 23 November 2012
(This article belongs to the Special Issue Biological Implications of Climate Change)
View Full-Text   |   Download PDF [802 KB, uploaded 23 November 2012]
Abstract: Species endemic to mountains on oceanic islands are subject to a number of existing threats (in particular, invasive species) along with the impacts of a rapidly changing climate. The Lord Howe Island endemic palm Hedyscepe canterburyana is restricted to two mountains above 300 m altitude. Predation by the introduced Black Rat (Rattus rattus) is known to significantly reduce seedling recruitment. We examined the variation in Hedyscepe in terms of genetic variation, morphology, reproductive output and demographic structure, across an altitudinal gradient. We used demographic data to model population persistence under climate change predictions of upward range contraction incorporating long-term climatic records for Lord Howe Island. We also accounted for alternative levels of rat predation into the model to reflect management options for control. We found that Lord Howe Island is getting warmer and drier and quantified the degree of temperature change with altitude (0.9 °C per 100 m). For H. canterburyana, differences in development rates, population structure, reproductive output and population growth rate were identified between altitudes. In contrast, genetic variation was high and did not vary with altitude. There is no evidence of an upward range contraction as was predicted and recruitment was greatest at lower altitudes. Our models predicted slow population decline in the species and that the highest altitude populations are under greatest threat of extinction. Removal of rat predation would significantly enhance future persistence of this species.
Keywords: climate change; genetic variation; growth rates; population growth climate change; genetic variation; growth rates; population growth
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Export to BibTeX |
EndNote


MDPI and ACS Style

Simmons, C.L.; Auld, T.D.; Hutton, I.; Baker, W.J.; Shapcott, A. Will Climate Change, Genetic and Demographic Variation or Rat Predation Pose the Greatest Risk for Persistence of an Altitudinally Distributed Island Endemic? Biology 2012, 1, 736-765.

AMA Style

Simmons CL, Auld TD, Hutton I, Baker WJ, Shapcott A. Will Climate Change, Genetic and Demographic Variation or Rat Predation Pose the Greatest Risk for Persistence of an Altitudinally Distributed Island Endemic? Biology. 2012; 1(3):736-765.

Chicago/Turabian Style

Simmons, Catherine L.; Auld, Tony D.; Hutton, Ian; Baker, William J.; Shapcott, Alison. 2012. "Will Climate Change, Genetic and Demographic Variation or Rat Predation Pose the Greatest Risk for Persistence of an Altitudinally Distributed Island Endemic?" Biology 1, no. 3: 736-765.


Biology EISSN 2079-7737 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert