The interactions between pairs of native and alien plants via shared use of pollinators have been widely studied. Community level studies however, are necessary in order to fully understand the factors and mechanisms that facilitate successful plant invasion, but these are still scarce. Specifically, few community level studies have considered how differences in invasion level (alien flower abundance), and degree of floral trait similarity between native and invasive species, mediate effects on native plant-pollinator communities. Here, we evaluated the role of alien species on overall plant-floral visitor network structure, and on species-level network parameters, across nine invaded coastal communities distributed along 205 km in Yucatán, México that vary in alien species richness and flower abundance. We further assessed the potential the role of alien plant species on plant-floral visitor network structure and robustness via computational simulation of native and invasive plant extinction scenarios. We did not find significant differences between native and alien species in their functional floral phenotypes or in their visitation rate and pollinator community composition in these invaded sites. Variation in the proportion of alien plant species and flower abundance across sites did not influence plant-pollinator network structure. Species-level network parameters (i.e., normalized degree and nestedness contribution) did not differ between native and alien species. Furthermore, our simulation analyses revealed that alien species are functionally equivalent to native species and contribute equally to network structure and robustness. Overall, our results suggest that high levels of floral trait similarity and pollinator use overlap may help facilitate the integration of alien species into native plant-pollinator networks. As a result, alien species may also play a similar role than that of natives in the structure and stability of native plant and pollinator communities in the studied coastal sand dune ecosystem.

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During the rainy season, the tropical deciduous forest (TDF) supposedly represents an abundance of biomass for sheep and goats. Nevertheless, quantitative estimations of feed intake during the rainy season are lacking. This study investigated the feeding behaviour of sheep and goats in a TDF in Mexico and quantified their nutrient intake during the rainy season. Plant species (PS) consumed, size and weight of bites, and nutritional quality were determined by continuous bite monitoring through direct observation. Adult ewes (n = 3) and goats (n = 3) were observed in their grazing circuits (4 h/day) for 12 days during the rainy season. Sheep and goats consumed 61 PS and performed a similar median number of bites (1751 vs 2053 bites/day, respectively; P > 0.05). Although they shared 52.5% of the PS consumed, only seven PS contributed most of the dry matter intake (DMI) for sheep (96.7%) or goats (90.5%). Sheep consumed more grass than goats (79.8% vs 48.3% of their DMI, respectively), whereas goats ate more shrubs than sheep (30.0% vs 7.6% of their DMI, respectively). The diet ingested by goats included more polyphenols (P < 0.05) and a higher frequency of larger and heavier bites than sheep (P < 0.05). Sheep reached 61.3% and 57.7% of their metabolisable energy and crude protein maintenance requirements. Similarly, goats covered 63.3% of their metabolisable energy and 108.2% of crude protein requirement. Although the main ration of sheep and goats was composed of similar PS, their different feeding behaviour resulted in different macronutrient consumption.