TY  - JOUR
T1  - Measuring Associations Between <I>Granivorous grassland</I> Bird Species and Between the Bird Species and Winter Habitat in Northwestern Mexico
AU - Corral-Rivas, Jose Javier AU - Solis, Martin E. Pereda AU - Martinez, G. Jose Hugo AU - Alferez, Federico Rosales AU - Wehenkel, Christian AU - Casio, Hector Herrera 
JO  - Research Journal of Biological Sciences
VL  - 5
IS  - 11
SP  - 713
EP  - 721
PY  - 2010
DA  - 2001/08/19
SN  - 1815-8846
DO  - rjbsci.2010.713.721
UR  - https://makhillpublications.co/view-article.php?doi=rjbsci.2010.713.721
KW  - Mexico
KW  -Kendall coefficient
KW  -Permutation test
KW  -vegetation attributes
KW  -Aimophila cassini
KW  -chihuahuan desert
AB  - Researchers evaluated the usefulness of two statistical methods, not used in ornithological studies to measure associations between granivorous grassland bird species and between the same species and seven different vegetation characteristics. The study was carried out in winter in the region of Cuchillas de la Zarca in Northwestern Mexico. Kendall’s coefficient showed little consistency in the determinations and only 2.19% of the associations between species were significant (p&lt;0.05). <I>Ammodramus bairdii</I>, <I>Ammodramus savannarum</I> and <I>Sturnella magna</I> were positively and significantly associated as were <I>Aimophila cassini</I> and <I>Passerculus sandwichensis</I>. Gregorius’s method was more consistent in determining the association (A) between <I>Granivorous grassland</I> birds (&#945;) and vegetation features (&#946;) with 48.9% of the estimations being significant. A total of 12 species were associated with shrub height, 7 with grass height, 19 with herbaceous height, 13 with shrub cover, 16 with grass cover, 18 with herbaceous cover and 14 with other types of cover such as superficial decomposing organic material. Researchers conclude that these statistical methods may be of greater utility in ornithological studies than their historical absence from this branch of biology indicates.
ER  -