Pollinating insects are decreasing worldwide in abundance, biomass, and species richness, affecting the plants that rely on pollinators for fruit production and seed set. Insects are often sensitive to high temperatures. The projected temperature increases may therefore severely affect plants that rely on insect pollinators. Highly specialized mutualisms are expected to be particularly vulnerable to change because they have fewer partner options should one partner become unavailable. In the highly specialized mutualism between fig trees and their pollinating fig wasp, each fig species is pollinated by only one or a few wasp species. Because of their year‐round fruit production, fig trees are considered a keystone resource for tropical forests. However, to produce fruits, wild fig trees need to be pollinated by fig wasps that typically travel a long one‐way trip from the tree donating pollen to the tree receiving pollen. In a few previous studies from China and Australia, increasing temperatures dramatically decreased fig wasp lifespan. Are these grim results generalizable to fig mutualisms globally? Here, we use survival experiments to determine the effect of increasing temperature on the lifespan of Neotropical fig wasps associated with five common Panamanian Ficus species. Experimental temperatures were based on the current daytime mean temperature of 26.8°C (2SD: 21.6–31.7°C) and the predicted local temperature increase of 1–4°C by the end of the 21st century. We found that all tested pollinator wasp species had a significantly shorter lifespan in 30, 32, 34, and 36°C compared to the current diurnal mean temperature of 26°C. At 36°C pollinator median lifespan decreased to merely 2–10 h (6%–19% of their median lifespan at 26°C). Unless wasps can adapt, such a dramatic reduction in lifespan is expected to reduce the number of pollinators that successfully disperse to flowering fig trees, and may therefore jeopardize both fruit set and eventually survival of the mutualism.

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In Borneo, the forest type that supports the largest number of species, the tropical lowland rainforest, is decreasing rapidly. To estimate what is the general effect of this habitat degradation and loss on birds, this study looks at the easily visible Black-and-Red Broadbill nests that were surveyed along the Kinabatangan river in eastern Sabah, Malaysian Borneo, and answers the following questions: (i) what is the current density of the population of the Black-and-Red Broadbill between Batu Putih and Bilit, along the Kinabatangan river, (ii) is the abundance of nests correlated with the surrounding habitat type (forest or disturbed area), and (iii) do Black-and-Red Broadbills need and/or use the riparian zone at the riverbank for nesting sites. During this study, a 55.6 kilometre river transect was surveyed for 3 days, and nests that were found were recorded. This study found that Black-and-Red Broadbills nests were significantly more often located in areas with a higher proportion of forest habitat type (compared to disturbed habitat type). Furthermore, this study shows that Black-and-Red Broadbills need branches and sticks at the river’s edge to build their nest on, so they are profiting from the riparian zones along the river. Therefore we recommend enhancement of nesting opportunity by artificially providing above-water nesting sites along the river edge.