Agriculture Reference
In-Depth Information
pollinator communities may vary both locally and regionally. We recom-
mend transect walks within agricultural fields to assess the status of pol-
linator communities of entomophilous crops. It is especially important to
train field workers in sampling techniques and pollinator taxonomy since
variations in skill have been shown to induce bias and reduce data quality.
In addition to visitation frequencies, data on the quality of each visit is
important for measuring the effectiveness of pollination.
20.5
IDENTIFICATION OF IMPORTANT POLLINATORS
Through intensive monitoring, the most frequent visitors to a particular
crop species can be identified. However, pollinators vary in their effec-
tiveness in initiating seed set. Fidelity to particular plant species, body
size and morphology, and physical movement within and among flowers
all affect pollination quality. The importance of each pollinator species is
a product of the visitation frequency and the quality of each visit. Visita-
tion quality of the most frequently observed pollinators should be investi-
gated by presenting flowers to single visits of particular pollinator species
(Kjohl et al., 2011).
20.5.1 POLLINATOR RESPONSES TO POTENTIAL CLIMATE
CHANGE SCENARIOS
Pollinators may respond to climate change in different ways, depending on
the system under study and climatic variable in focus. Pollinators may also
respond in different ways depending on whether the scale is individuals
vs. populations or local vs. landscape (Kjohl et al., 2011). Pollinators may
change behavior in response to shifts in climate. Observations of pollina-
tors in experimentally warmed greenhouses reveal behavioral responses
to climate change that may be important for flower visitation. The time
taken for thermoregulation at higher temperatures comes at the cost of
foraging, with negative consequences for pollination. It is likely that pol-
linators will change their activity patterns as temperature increases, in turn
changing the efficiency of pollen removal and deposition. For this reason,
it is important to investigate taxonomic differences in pollinators' ability
to regulate body temperature and avoid overheating.
