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114 ÍVI. Methods of a zoocoenological analysis
There are two conseguences: a zoocoenologist must collect most of the
animals from the field, and the material identified in the laboratory must be
analysed by methods that allow delimitation of the individual associative
categories. Ihese are also warnings that, in the place of phytocoenological
characteristics, or in addition to their use, we need other characteristics that
will help to achieve our goals.
Therefore, all zoocoenological research has two methodological stages:
censusing the association, and analysing it.
The aim of the census is to collect information about the totality of the
animal assemblages of a given area, the entirety of its constituent population.
This definition indicates that this phase is nearly identical with the task of
faunistical research. Indeed, the difference is only that the aim of faunistics
is only to identify all species living in the study area, while the coenologist
also wants to know about their roles. In practice, a zoocoenological collection
phase is different from the faunistical one, because it has to be performed so
that the collected material is suitable for a subsequent coenological analysis.
The first criterion is that the overall picture would not only reflect the
constituent species, but also of their density and relative abundance. It is
impossible to use the same survey method for all groups, yet it is a necessary
condition that the methods used for a given group be identical in all cases.
Thus, for example, on a wheat field we should take the same number of soil
samples (this would be an error - as the size of the field needs to be taken
into account, otherwise the sampling intensity will be different); on the soil
surface, we ought to examine the same number of quadrats; from the plants
(in order to study endophytes) we should take the same number of samples,
and; from the plants, we collect animals by sweep netting, using the same
number ofsweeps taken at the same time ofthe day. An exhaustive sampling,
due to the complicated life patterns of animals, needs a set of different
methods, thus the sampling methods can be grouped into three:
a) collecting methods can be used when full compilation of the studied
assemblage can be attained by methods used in faunistical studies
b) incubating methods need to be used when a population cannot be
properly sampled by any methods, because of its hidden way of life, or
because it is “hidden” within another population, thus its presence is impossible
to detect using traditional collecting methods. Such methods need to be
employed when censusing animals living in stems, seeds of galls. Also,
incubation is necessary to assess the degree of infestation by endoparasites,
i.e. to what degree a given parasite population is present in the zoocoenosis.
c) observational methods are to be used when neither collecting nor
incubation methods are usable, either because of the high vagility of animals,
or the strong dispersion of semaphoronts. In such cases, only observations can
enlighten us as to how these animals live in the community, how they spend
their time, and what role they fulfil. Thus, observation — be that under field
conditions if possible, or in the laboratory, if necessary - firmly belongs to the