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Simple Summary: The European native spider mite Tetranychus ludeni Zacher (Acari: Tetranychidae) is an invasive species which attacks many economically important crops. Investigations into how different factors affect its dispersal probability and distance help better understand its population management and enable researchers to perform invasion evaluations. Here, we tested the effect of age and density on dispersal probability and distance. We show that older females that are capable of producing more eggs within 24 h were more likely to disperse and moved longer distances than younger ones with fewer eggs. Older females spread most of their eggs out of their natal habitats and over longer distances, which reduced competition and increased offspring fitness. Our results also indicate that females exhibited significantly increased dispersal probability and distance with an increase in population density to avoid crowding. The synchronization of dispersal and reproduction, along with the positive density-dependent dispersal strategy, may facilitate the habitat colonization and invasion speed of T. ludeni. The dispersal strategies of a species can affect its invasion success. Investigations into the dispersal strategies of invasive species in relation to different factors help improve our understanding of invasion mechanisms and provide knowledge for population management and invasion evaluation. Tetranychus ludeni Zacher (Acari: Tetranychidae) is an invasive species which is native to Europe but is now cosmopolitan. Here, we examined the effects of age and density on dispersal in mated females. Our results show that older females that are capable of producing more eggs within 24 h were more likely to disperse and moved longer distances than younger ones with fewer eggs. Older females spread most of their eggs out of their natal habitats and over longer distances, which reduced competition and increased offspring fitness. Females exhibited significantly increased dispersal probability and distances with an increase in population density to avoid crowding. The synchronization of dispersal and reproduction, along with the positive density-dependent dispersal strategy, may facilitate the habitat colonization and invasion speed of T. ludeni. [ABSTRACT FROM AUTHOR]

Life history strategies of a species may affect its invasion success. Here, we used a haplodiploid pest, Tetranychus ludeni Zacher (Acari: Tetranychidae), which is native to Europe but now cosmopolitan, to investigate its life history strategies in relation to its dispersal tendency and distance. We tested whether and how dispersal influenced survival, lifetime fecundity, age-specific reproduction, and life table parameters of mated females. We show that mated females did not trade off their survival and lifetime reproductive output with dispersal but adjusted their resource allocations during different reproductive stages depending on whether and how far they dispersed. Long-distance dispersers invested more in dispersal in their early life while resident mites and short-distance dispersers invested more in reproduction during their early life. These resource allocation strategies may allow long-distance dispersers to explore the novel environment more effectively without compromising lifetime reproductive fitness, contributing to the invasion success of T. ludeni. [ABSTRACT FROM AUTHOR]

With significant surge of international trade in recent decades, increasingly more arthropod species have become established outside their natural range of distribution, causing enormous damage in their novel habitats. However, whether a species can colonize its new environment depends on its ability to overcome various barriers which may result in establishment failure, such as inbreeding depression and difficulty to find mates. Here, we used a haplodiploid pest, Tetranychus ludeni Zacher (Acari: Tetranychidae), which is native to Europe but now cosmopolitan, to investigate whether its reproductive strategies have facilitated its invasion success, providing knowledge to develop programs for prediction and management of biological invasions. We show that inbreeding had no negative influence on female reproductive outputs and longevity over 11 successive generations, allowing mother-son and brother-sister mating to occur at the invasion front without adverse consequences in fitness. Virgin females produced maximum number of sons in their early life to ensure subsequent mother-son mating but later saved resources to prolong longevity for potential future mating. Females maximized their resource allocation to egg production immediately after mating to secure production of maximum number of both daughters and sons as early as possible. Furthermore, mated females with mating delay increased proportion of daughters in offspring produced to compensate the loss of production of daughters during their virgin life. We suggest that the lack of inbreeding depression in successive generations and the ability to adjust resource allocations depending whether and when mating occurs may be the key features that have facilitated its invasion success. [ABSTRACT FROM AUTHOR]