基本HTML版本
Intl. J. of Super Species Research 2012, Vol.2, No.1, 1
-
6
http://ijssr.sophiapublisher.com
2
studies describing bird-mite relationships and
elucidating the functional significance of feather mites
(Bridge, 2003). Previous studies (e.g. Gaud and Atyeo,
1996) found that feather mites can be associated to
true parasites, thus correlational studies of birds and
feather mites needs to be interpreted with caution.
1 Aims and Objectives
This study aimed to investigate if mite loads differ
across species and to test if factors, such as age, sex
and body condition could explain trends in mite
abundances. It is hypothesized that feather mite
density will be positively associated with poor body
condition and that mite loads are affected by sex and
age in a species. In addition, this paper investigated the
preferences for certain microhabitats on a wing and by
roosting several birds overnight, this study examines
how mite distributions change over time as a result of
changing environmental conditions/bird activity.
2 Methods and Analysis
Study area- Data was collected from 31st of March
until 4th of April 2011 at Urra Field station near
Sorbas, in Almeria province, south-east Spain. Annual
rainfall is low during all seasons (ca 300 mm), mean
temperatures of 17
℃
but regularly rise to over 40
℃
.
The area has been classified as semi-arid
thermomediterranean (Rivas-Martinez et al., 2001)
and is considered as the driest place in Europe.
Sampling- Birds were captured using mist nets around
the Urra Field centre by authorised bird ringers. Nets
were set when birds were most active (6 am~12 pm
and 5~10 pm). In addition to the standard data
collected by the ringers (species, sex, age, weight, tail
and wing measurements), the following information
was recorded: body condition, weight, fat and pectoral
muscle levels were used as a proxy for body condition
for each bird. Pectoral muscles and fat levels were
scored for each bird, following BTO data collection
and biometrics standards (2001) (See appendix 1 and
2, respectively).
Mite distribution on the wing-Feather mites on
primary and secondary feathers was counted using
handheld magnifying glasses. Mites found on the right
wing were used in the final analysis because an initial
comparison of feather mite abundances on the left and
right wings showed that abundances were highly
correlated (Pearson correlation R=0.975, df=71,
p<0.001). The spatial distribution of mites on the right
wing was recorded by dividing the wing into several
categories: 1=primaries 1-3 (P1-3), 2=primaries 4-6
(P4-6), primaries 7-10 (P7-10), 4=secondaries, and
5=random distribution. Scores were assigned to each
wing, depending on where more than 50% of the
mites were found.
Diurnal changes in mite abundances-A number of