Previous research<\/a> has focused on how temperature changes affect bees, finding that certain groups are more vulnerable to hotter temperatures.<\/p>\n But our new study<\/a> shows rising carbon dioxide (CO\u2082) levels may also be putting pollinators \u2013 such as bees and hoverflies \u2013 at risk. <\/p>\n Larger bees are the most vulnerable. We found populations of big bees \u2013 including Bombus asiaticus and Xylocopa pubescens \u2013 were smaller and less genetically diverse in areas with high CO\u2082. Small-bodied pollinators, however, may actually do better in higher-CO\u2082 environments. <\/p>\n A dire situation<\/p>\n In Australia and around the world, we are facing a pollinator crisis<\/a>. There are several reasons for this, including the loss and degradation of wild pollinator habitat, the introduction of the European honey bee and other invasive species, and the use of broad-spectrum pesticides.<\/p>\n But climate change \u2013 driven by human-made greenhouse gases including CO\u2082 emissions \u2013 is another key factor. Australia contributes to higher CO\u2082 levels as the second-largest fossil fuel exporter<\/a> in the world.<\/p>\n Elevated CO\u2082 levels can affect pollinators by reducing how much protein<\/a> is in flower pollen. Having more CO\u2082 in our atmosphere may also change the chemical make-up of nectar<\/a>, for example reducing how much sugar it contains. Both factors influence how pollinators develop and survive.<\/p>\n Other research<\/a> suggests higher CO\u2082 concentrations could impact how pollinators\u2019 bodies function, for example by accelerating how quickly they break down fats<\/a>.<\/p>\n Read more: What we studied<\/p>\n In our latest study<\/a>, we examined how bees and hoverflies coped with different levels of CO\u2082 across 25 sites. This is the first time researchers have investigated how natural changes in CO\u2082 levels affect pollinators. <\/p>\n While our study was conducted in Pakistan, it is relevant to pollinator networks in Australia and around the world, given that CO\u2082 levels are rising globally. Importantly, we controlled for other factors that may affect the number and distribution of bees and hoverflies, including altitude, temperature, humidity and rainfall.<\/p>\n Our results suggest pollinators respond to variations in CO\u2082 in different ways. Specifically, smaller pollinators may actually do better in higher-CO\u2082 environments. In contrast, larger-bodied pollinators were less abundant in areas with more CO\u2082.<\/p>\n We identified Xylocopa and Amegilla bees, two genera found in Australia, as being particularly vulnerable to increased CO\u2082 levels. Ceratina and Lasioglossum bees are two examples of smaller-bodied Australian genera that did well in higher-CO\u2082 environments.<\/p>\n The pubescent carpenter bee is a larger-bodied species that is vulnerable to rising CO\u2082 levels. Why big bees matter<\/p>\n These findings are concerning for several reasons.<\/p>\n Existing evidence<\/a> shows larger-bodied bees such as Bombus are already more vulnerable to climate change. This is because they tend to retain more heat and don\u2019t cope as well in dry conditions. Big bees also have higher metabolic demands than smaller pollinators, meaning they need more resources to keep their bodies functioning.<\/p>\n Large bees are among our most effective pollinators<\/a>. They typically carry and deposit more pollen than smaller-bodied pollinator species. They also fly longer distances, meaning they can transport seeds and pollen to help plants reproduce and spread their genes<\/a> to new places. <\/p>\n Other research<\/a> suggests flowers have even evolved to match pollinators with particular body sizes. We see this in Australia with Melastoma. This plant\u2019s impressive flowers are most effectively pollinated by large pollinators such as Xylocopa bees, which use vibrations to release pollen from flowers.<\/p>\n Read more: So, what can we do?<\/p>\n Here are four practical ways we can help our larger pollinators thrive in a warming world. <\/p>\n protect their habitat by preventing further land clearing<\/a>, for example to make room for more livestock farms<\/p>\n ensure pollinators have access to wildlife corridors to help them move to areas that are naturally lower in CO\u2082, such as dense forests<\/a><\/p>\n plant more bee-friendly trees<\/a>, with some Australian examples being Eucalyptus, Corymbia, Angophora, Melaleuca, Banksia and Brachychiton<\/p>\n maintain populations of larger-bodied bees by reducing other threats such as competition from introduced honey bees<\/a>, to ensure they have the genetic diversity<\/a> to adapt to rising CO\u2082 levels.<\/p>\n To protect our pollinators in a rapidly changing climate, we must act now. Ensuring their habitat remains intact and curbing our greenhouse gas emissions are vital first steps.<\/p>\n
\n Native pollinators need more support than honeybees in Australia \u2013 here\u2019s why<\/a><\/p>\n![\"A](\"https:\/\/www.newsbeep.com\/il\/wp-content\/uploads\/2026\/07\/file-20260702-57-py04yh.JPG\")
<\/p>\n
\n Waseem Akram<\/p>\n
\n How will Australian native bees cope with climate change? Their nests hold a clue<\/a><\/p>\n