20th International Congress of Arachnology

183 / 232

Student - poster presentation
Female preference for male chemotactile
cues in Pardosa milvina(Araneae,
Lycosidae)
*Michael T. Stanley, Ann L. Rypstra
700 E High St, Oxford, Miami University, OH 45056, USA
Understanding the types of information organisms use
to make mating decisions is a critical part of studying
sexual selection. In the wolf spider Pardosa milvina,
both air- and substrate-borne chemical cues from females
attract males, and visual aspects of male courtship
impact female mate choice. Few studies, however, have
examined the impact of male chemical cues deposited on
a substrate (chemotactile cues) on female preference. We
first monitored the amount of time females spent on male
chemotactile cues and the amount of movement females
performed on these cues, when the cues were from males
that differed in quality (well-fed or food limited) and
were not physically present. We found that the time that
females spent and the amount of movement females
performed did not differ between male chemotactile
cues. Next, we examined the time it took the female to
approach and the time they spent in association with a
male sequestered under a glass vial, where half the males
were surrounded by their own chemotactile cues and half
the males were not. We also monitored the number of
male courtship attempts, as well as the number of female
attempts to interact with the male. The presence of male
chemical cues had no effect on the time it took a female
to approach or the time the female spent in association
with the sequestered male. However, the frequency of
courtship bouts performed by the male was correlated
with the time the female spent near him. In addition,
the frequency with which the female appeared to have
her attention directed toward the male was related to
his courtship activity. Taken together, these experiments
confirm that P. milvina females focus on the visual
courtship display of males and suggest that they do not
use chemical cues to recognize or assess male quality.
Keywords: sexual selection, mate choice, chemotactile
cues, courtship
Poster Presentation
Low-input conventional farming supports
biodiversity of spiders in eastern Poland
Marzena Stańska1, Izabela Hajdamowicz1, Anna Król1,
Andreas Hirler 1 , Łukasz Nicewicz 1, Jarosław Stalenga2
1Siedlce University of Natural Sciences and Humani-
ties, Institute of Biology, Prusa 12, 08-110 Siedlce,
Poland; 1Institute of Soil Science and Plant Cultiva-
tion, State Research Institute, Czartoryskich 8, 24-100
Pulawy, Poland
Numerous studies show the negative influence of intensified
agriculture practices on biodiversity of different groups of
invertebrates, including spiders. To conserve biodiversity
in European farmlands, different measures have been
implemented for last years within EU Common Agri-
cultural Policy, of which one of the most important is the
agri-environmental scheme. There is still not much data
concerning the effect of low-input conventional farming
systems on spider communities. Our study aims to compare
spider assemblages in winter cereals in low-input conven-
tional and organic farming systems in high nature value
farmlands of eastern Poland. The research was conducted
in 2012 and 2013, on 28 and 24 study plots, respectively.
The plots were divided in two categories: low-input con-
ventional farming plots where only small doses of synthetic
fertilizers and pesticides were used and organic farming
plots (in agri-environmental scheme) where neither pesti-
cides nor synthetic fertilizers were applied. Epigeic spiders
were collected once a month from April till July in both
years of study. They were caught by pitfall traps operating
two weeks every month on each study plot. In organic fields
the number of specimens was higher in comparison to
conventional plots (14,797 and 14,599 specimens, respec-
tively), while the species richness and diversity showed the
reverse tendency (98 species, H’=2,44 in organic plots and
102 species, H’=2,54 in conventional fields). Differences in
numbers of specimens and species richness were not statis-
tically significant. For both types of study plots Linyphiidae
and Lycosidae families were the most numerous in terms of
specimen numbers. The linyphiids were more abundant in
conventional plots and the lycosids were more numerous
182 DENVER MUSEUM OF NATURE & SCIENCE REPORTS | No. 3, July 2, 2016
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