TITLE

Comparative demographic analysis in contrasting environments of Magnolia dealbata: an endangered species from Mexico

AUTHOR(S)
Sánchez-Velásquez, Lázaro; del Pineda-López, María
PUB. DATE
January 2010
SOURCE
Population Ecology;Jan2010, Vol. 52 Issue 1, p203
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The study of population regulation and demography in natural habitats is critical for the conservation of rare and endangered species. We address the impact of cattle exclusion on the demographics of Magnolia dealbata (Magnoliaceae), an endangered species according to IUCN and Federal Mexican laws. Sixteen permanent plots were established, eight of which were enclosed to livestock, in the mountain cloud forest in Coyopolan, Mexico, which has the largest population of M. deadlbata. Censuses of the plots were undertaken annually during three annual cycles to record seed number, recruitment, mortality, and growth (defined as length and diameter at breast height). The effects of two treatments (with and without livestock exclusion) on the dynamics of M. dealbata were investigated using transition matrix models and life table response experiment (LTRE) analysis. Contrary to expectations, there was no significant effect of cattle exclusion on population growth rates ( λ). Furthermore, the λ, estimated from the mean transition matrix for both treatments was greater than one. The transitions with the highest elasticity values were similar between the two treatments, while reproductive stage contributed more to differences in population growth rate and were less variable than the non-reproductive stage. LTRE analysis showed that treatment differences had little effect on λ. Livestock exclusion appears to lead more to differences in the arrangement of the values of the transition matrix than to the rate of population growth for M. dealbata.
ACCESSION #
47161034

 

Related Articles

  • CLAIRE DANES: BARES HER ANIMAL INSTINCTS. Richart, Elizabeth // Marie Claire (US Edition);Jul2003, Vol. 10 Issue 7, p54 

    This article focuses on the Australian Koala bears who are in the list of endangered species. Approximately 80 percent of Australia's original koala habitat has been decimated to make way for housing projects. Koalas like to live anywhere they see an edible eucalyptus tree. Koalas can consume...

  • Endangered and Threatened Wildlife and Plants; Endangered Status and Designations of Critical Habitat for Spikedace and Loach Minnow. Jacobson, Rachel // Federal Register (National Archives & Records Service, Office of;2/23/2012, Vol. 77 Issue 36, p10810 

    The article focuses on the settlement agreement associated with the changes in the habitat of two declining fish species spikedace (Meda fulgida) and loach minnow (Tiaroga cobitis) from threatened to endangered habitat given by the U.S. Fish and Wildlife Service. It is stated that changes...

  • Proposed Rules: Steelhead Trout (Oncorhynchus mykiss).  // Endangered Species Bulletin;May/Jun2000, Vol. 25 Issue 3, p35 

    Reports on the proposed inclusion of Steelhead Trout to the list of endangered species by the Fish and Wildlife Service and National Marine Fisheries Service in the U.S. Widespread degradation of aquatic habitats; Reasons for the decline of steelhead populations.

  • A different species of agreements. Zaffos, Joshua // High Country News;5/28/2012, Vol. 44 Issue 9, p3 

    The article discusses issues concerning voluntary conservation to address listings of endangered species in the Gunnison sage grouse. It mentions that the working group is committed to a voluntary plan with the U.S. Fish and Wildlife Service to preserve the Gunnison grouse and its public-land...

  • A Numbers Puzzle.  // Weekly Reader News - Edition 4;10/8/2004, Vol. 86 Issue 5, p4 

    Explores scientists' census of giant pandas in China. Estimated number of endangered pandas; Effect of human activity on the habitat of pandas; Technology used by scientists to track pandas; Protection of pandas.

  • ENDANGERED SPECIES.  // World Almanac for Kids;1999, p20 

    No abstract available.

  • Protection or Paralysis? Helsdon, Jeff // Ontario Out of Doors;Feb2010, Vol. 42 Issue 1, p46 

    The article explores the impact of the Endangered Species Act (ESA) towards the agriculture, landowners, and individuals involved in hunting and fishing in Ontario. It states that the Committee on the Status of Species at Risk in Ontario (COSSARO) would determine the listed species and some...

  • ENDANGERED SPECIES.  // World Almanac for Kids;1997, p23 

    This article provides information on endangered species. When an animal becomes less and less plentiful on one part of the earth or in the entire world, the animal is said to be endangered or threatened. The U.S. Department of the Interior keeps track of endangered and threatened species. Over...

  • ENDANGERED SPECIES.  // World Almanac for Kids;2000, p38 

    This article provides information on endangered species. When an animal becomes less and less plentiful on one part of the Earth or in the entire world, the animal is said to be endangered or threatened. The U.S. Department of the Interior keeps track of endangered and threatened animals....

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics