Are the Interactions between Oaks and Pre-Dispersal Seed Predators Retained in Urban Environments? An Analysis of Two Quercus Species in Southern Mexico City

As urbanization proceeds, natural ecosystems surrounding cities are transformed, but usually some elements persist, notably trees from forest ecosystems. However, it is still unknown the extent to which isolated trees, immersed in an urban matrix, maintain their interactions with insects that feed on seeds. In this work we analyzed pre-dispersal seed predation by two main groups of insects, weevils (Coleoptera; Curculionidae) and moths (Lepidoptera: Tortricidae), whose larvae acorns oak species (Quercus rugosa Q. castanea). We compared these between located a protected forested area matrix. Our hypothesis was that, since depends insect dispersal, would have lower levels than forest. A second hypothesis, based reports exhibit larger dispersal distances weevils, higher respective proportions trees. Finally, expected moth increase size, as does weevils. collected 1200 (ten per species) nearby highway southern Mexico City. From whole sample, 17.3% were predated 3.8% moths. The probability (0.30) those (0.07), confirmed first hypothesis; tree identity did not significant effect proportion acorns. When only analyzed, weevil both species, although having large (Q. rugosa, 0.93), small castanea, 0.63). Inversely, castanea (0.37) (0.07). Seed decreased similarly for so failed find support our hypothesis. positive relationship size found castanea; affect larvae. Therefore, matrix harbor smaller populations predators feeding maintained, points importance conservation biodiversity.