Entomologist: several new insect species reach Estonia annually
University of Tartu entomologist Mati Martin says that the numbers of lice and fleas have decreased significantly, but every year several new insect species arrive in Estonia. The sea buckthorn fruit fly, for example, has made growing sea buckthorn pointless in many places.
"Once we carried out a small study — it was more than ten years ago — and at that time we found that about 15,000 insect species could be identified in Estonia. Looking at studies done in neighboring countries, one could assume that Estonia has 24,000 insect species or even more," Martin said.
The abundance of human parasites such as lice and fleas has decreased considerably. "With the expansion of trade, insects living on food products move very often and very quickly together with goods," Martin noted. "Right now it is very fashionable to install stone paving around houses and on many courtyards. But stone paving is a very good habitat for soil‑dwelling ants, which are tiny black ants. There have been enormous numbers of them lately."
Martin has noticed that because lawns are mowed very frequently nowadays, and when dandelions start growing there, for some reason ants like them very much. "I did research in my own garden, and of ten dandelions growing in the lawn, nine had ant nests in the soil around them," Martin said.
There are also large differences between the insect communities of western and eastern Estonia. "Insects have divided up the vegetation period — from early spring until almost the arrival of snow, some insect species are active, and some species are active even under the snow."
"Insect allergies are a serious problem; Estonia has even had fatal cases, and everything happens quite quickly," the insect scientist pointed out.
"Blackflies bite very painfully; they last throughout the summer, and even in September one can still fall victim to them," Martin noted.
Insects develop in cycles. Three to four years is a normal cycle; in the fifth, sixth and seventh years, for some reason, their numbers become very high and then we see them everywhere. "If they develop according to a normal cycle, we do not see them much," Martin explained, referring to why ladybirds are scarce this year. "For example, right now there are relatively many webbing moths. Even under normal conditions, insect abundance fluctuates from year to year."
Every year, according to Martin, several new insect species arrive in Estonia. "The sea buckthorn fruit fly is one of the latest to reach us, and it eats sea buckthorn berries with great appetite. In some places, growing sea buckthorn has already become pointless," the scientist said.
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