In this manual we have included a description
of the structure and sequence for this field study activity, determining the main
characteristics of invertebrate populations in different habitats and environments and a
description of techniques for collection and census of invertebrates within the forest
litter and wood.
This field study has instructional video
featuring real students conducting the ecological field techniques in nature. Each video
illustrates the primary instructional outcomes and the major steps in accomplishing the
task including reporting the results.
Introduction
This study of forest invertebrates is primarily concerned with two objectives:
revealing patterns of invertebrate community structures (content) and collection
techniques (skills). Recently the strategy of invertebrate collections (especially
insects) has been criticized due to conservation issues and nature protection. In
particular, this applies to people (many of them children) who are fond of nature,
collecting butterflies. One way to limit invertebrate collecting is to study insect
populations using specific scientific techniques.
The study of diversity of species and numbers of animals is one of the main
objectives of ecological investigations. We consider the size of the population (numbers
of organisms) to be the most important characteristic of the species in a given community.
A number of other ecological indicators can be analyzed on the basis of numbers of
organisms, including the temporal and spatial diversity of faunas, since their level is
often regarded as an indicator of the state of an ecosystem.
The aim of this first forest invertebrate activity is the study of the main
characteristics of invertebrate populations in different habitats and environments, and it
is devoted to the study of forest litter and wood. The second activity is devoted
to insects found in the grass layer and tree crowns as well as flying
insects.
Some ethical considerations
Identification of species is an essential part of all zoological studies. At the same
time it is often quite difficult to accurately identify living subjects. In the case of
invertebrate organisms, it is necessary to analyze small moving parts such as number of
segments, hair, peculiarities of genital structure and location of ribs on wings, etc.)
Unfortunately, when researchers conduct serious scientific studies, animals are
sometimes killed. Moreover, it is often essential to carry out multiple collections of
several specimens representing the same taxon or sex. This is necessary in order to
accurately determine the species, as the main diagnostic parameters are often
subject to significant variability. Multiple collections are necessary as well when
conducting a number of specific ecological studies: study of population dynamics
and density of insect populations, influence of environmental factors on the morphological
features of individual's structure, in assessment of biotopic or substrate
diversity of species, etc.
According to the Law of the Russian Federation "On protection and conservation of
fauna" (Article 42) collection and "replenishment of zoological collections, which are
found in personal property of citizens - is prohibited, excepting collections, which
consist of hunting or fishing trophies".
Thus, at least in Russia, all zoological materials that are collected by students in
order to be stored at home or at school fall under this jurisdiction and are considered
illegal. Withdrawal of animals from nature is allowed only for specialized scientific
research establishments and public associations, which can ensure correct collection and
storage of zoological objects.
When performing educational research work with students, they should be limited to
methods of vital studies of invertebrates, ideally, without catching animals. If catching
of organisms is necessary for a specific study, then it is essential to comply with the
following rules:
Do not kill animals if it is not necessary;
Do not take organisms
outside of the habitats in which they have been caught. If they are taken outside the
boundaries of the habitat, they should be returned later;
Leave the sample site undamaged (put the upturned litter back, as well as
stones, logs, boards, etc.).
General procedures for collection and census of invertebrates
While carrying out this activity, students will have to deal with catching and
censusing of invertebrates. There is a specific technique for each ecological group
of invertebrates and, correspondingly, for each of their habitats.
However, not every technique for collecting is a technique for censusing. There are
several procedures for collection, which cannot be used for determination of the density
of invertebrate populations, - i.e. for estimation of a number of specimens per unit area
or unit of habitat volume. So, techniques of invertebrate collection such as catching
insects using food as bait or catching migrating animals are not techniques of censusing.
At best, some techniques for...
This was only the first page from the manual and its full version you can see in the
Our Paperback and eBooks on Amazon, Google Play and App Store
In this manual we have included a description
of the structure and sequence for this field study activity, determining the main
characteristics of invertebrate populations in different habitats and environments and a
description of techniques for collection and census of invertebrates within the forest
litter and wood.
Our Paperback and eBooks on Amazon, Google Play and App Store