Robust male condition must be favored and should be signaled to conspecifics via enhanced aggression and more highly expressed ornamental traits. One way that such robust condition, and thereby the expression of aggression and ornamental traits, can be assessed is via survival. In odonate adults, condition (in the form of lipid reserves, muscle mass and…
We marked and released 276 F-0 larvae of Ophiogomphus rupinsulensis in the fall of 2008 in a 99-m riffle (marking riffle) of a small, serially discontinuous, northern Wisconsin river (USA). We then recovered marked exuviae via exhaustive collecting on the banks of a 272-m sampling reach in which the marking riffle was located during spring…
Little is known about the ability of adult dragonfly individuals to survive into or over the winter in the Cape Floristic Region (CFR), a significant biodiversity hotspot in South Africa. Dragonfly species richness and abundance were recorded throughout winter and into spring in Jonkershoek Nature Reserve. Several environmental variables were also measured. Individuals of eight…
Food intake rate and diet composition have a high impact on all organisms and affect individual fitness, fecundity and mortality. Specimens in enclosures have to be fed in an adequate way and with minimum stress for the specimens. Adult dragonflies are flying hunters. In enclosures, they are usually fed by adding different kinds of adult…
The damselfly species Paracercion melanotum has been found to be the most abundant species in damselfly larval communities on Okinawa-zima Island in southwest Japan. To clarify differential susceptibility to predation, a possible factor affecting relative population densities in larval communities, between Paracercion melanotum and a less common damselfly species, Ischnura senegalensis, laboratory experiments were conducted…
Sympetrum striolatum (Charpentier, 1840) and S. vulgatum (Linnaeus, 1758) are two closely related Libellulidae that are widespread and common in Central Europe. The idea for this research originates from normally using saltwater shrimps for rearing young larvae, the observations of Sympetrum species laying eggs in seawater and the suggested ability of S. striolatum to colonize brackish water habitats.
Demography and territorial behavior of Hetaerina cruentata was studied along three lowland streams located at Norte de Santander department in the Colombian Andean region. Adult damselflies (N: 278) were individually marked, and using their recapture histories we estimated survival, longevity, sex ratio, age groups and population size at each location.
We investigated the effects of the presence of bladderwort plants on survival of early instar larvae of one coenagrionid and two libellulids in laboratory experiments. In all three species survival was reduced compared to treatments with a non-carnivorous submerged plant, with effective mortality that could be related to bladderwort being 19–45% dependent on the prey…
Remarkable flight performance is key to the survival of adult Odonata. They integrate varied three-dimensional architectures and kinematics of the wings, unsteady aerodynamics, and sensory feedback control in order to achieve agile flight. Therefore, a diverse range of approaches are necessary to understand their flight strategy comprehensively. Recently, new data have been presented in several…
Damselflies adapted to forest habitats are expected to be negatively affected by the disturbance of riparian forests, due to the change in insolation when trees are cleared. In this paper, we compare survivorship and behaviour of two populations of Heteragrion cooki by means of mark-recapture methods and focal observations of adults. We found similar densities…