Population Structures of Polistes Wasps (Hymenoptera, Vespidae) Nesting on Plants
Kherson Pedagogical University, Kherson, Ukraine
Informative processes in the population are realized in the form of behavior interactions at the level of individuals, colonies and supercolonies (Panov, 1983; Zhacharov, 1991).
The present study demonstrates the diversity of population structures and their relation to the environment as well as interspecies level of colony organization. Two Polistes species nest on plants in the Kherson region, South of Ukraine. P. dominulus is the species with a wide landscape spreading.
The size of this species population in intact biotopes of the Black Sea Reserve steppe is more than in the town outskirts.
P. chinensis is met in the reserve steppe very rarely since it prefers ruderal plant associations, i.e. vegetation at the early stages of succession.
In favorable years nest density of P. dominilus on the steppe vegetation is similar to that of P. chinensis on the ruderal plants.
Weather conditions, predators and parasites press, interspecies competition and anthropogenic impact restrict the population density.
Typological differences in behavioral organization of this species population system are connected with the nesting mode and its dynamics within the year and through the years. Population systems of the species under study are characterized by differentiation in the colonies producing off-spring.
P. dominulus colonies are formed haplometrotically, pleometrotically and by usurpation. After destroying the colony, renesting is rarely successful. P. chinensis colonies are founded by single queens in spring, and by queen and workers or only workers at the worker stage after destroying the primary nest.
At the colony level the species differences are conditioned by possible ways in the evolution of social systems in Polistes. It may appear to be the result of the divergence process: forming species sensitive and stable to social stimulation. This may create different mechanisms of supporting stability and survival.
Variations of population structures; both within and between species provide opportunities for comparative analysis of social systems; that widens our respective on the relationship: social structure – environmental complex.
Zoocenosis — 2001
Структура і функціональна роль тваринного населення в природних та трансформованих екосистемах: Тези I міжнародної конференції, 17-20 вересня 2001. – Дніпропетровськ: ДНУ, 2001. – С. 96-97.