There have been numerous projects all over the world that have strived to expand, restore and mitigate losses of native butterflies’ habitats. Some butterflies have been endangered or threatened therefore the scientists have conducted research on the reasons and possibilities. As a result it has been observed as well as experienced that there is a severe need and concern to practice restoration or improvement of the butterfly habitat that exist.
Each butterfly species belongs to its own combination of unique life history and habitat requirements. Yet, there are some principles that are fundamental to butterfly biology that play a significant role in planning habitat restorations.
You may not know that caterpillars are essentially herbivores and are specialists that feed on a particular kind or related kind of plants. The larval host plants and their presence in the right amount is one of the key factors that habitat restoration is dependent on. There are a number of butterflies that require the larval food plant to be of particular height, typical growth stage, close proximity to another resource and also exposed to the right amount of sunlight.
Adult butterflies tend to use a wider range of plants or food resources and the flight they have imparts them much more mobility. The tendency of adult dispersal varies from species to species. Some species migrate as a routine to long distances, while others are dependent on physical features for their dispersal – like few meters of open space, a hedge, a stream or a change in gradient. If these physical geographical features are absent they are limit their dispersal.
The species whose mobility levels are high can form ‘open’ or ‘loose’ populations but with no distinct boundaries. These kinds of species might have a relatively wide and continuous geographical dispersion. They are often looked upon as rare if found in low density within its range. On the other hand, in temperate regions 85 percent of butterflies might form ‘closed’ or ‘tight’ populations having discrete colonies yet have distinct geographical boundaries.
It is interesting to note that closed populations of butterflies might be restricted to typical geographical formations, early stage of vegetation or soil types which support vegetation. The closed populations are generally a part of ‘metapopulation,’ that are groups of local populations who occupy very distinct patches of habitat. As long as the habitat remains suitable the metapopulation can easily survive for many-many years.
Extinction of one colony of butterflies will be an offset by decolonization from another. Closed populations often become isolated due to the fragmentation or degradation of a habitat and become vulnerable and are susceptible to change in environment and locally variable conditions.
It is important to note that the adaptive ability of an isolated population of butterfly’s decreases since the gene pool doesn’t get refreshed by immigration any longer. Due to low dispersal ability the butterfly’s species face extinction.
Similar to insects, butterflies typically adapt to very precise, fine-scaled environmental conditions. The environmental conditions are very subtle and not easily discernible by a human observer – therefore meeting them is an essential factor in restoring habitat for butterflies in areas that are dominated by human beings.