Bumblebees might be at home in town and country but now researchers have found at least one species that is even more adaptable: it can survive underwater.

Scientists have revealed queens of the common eastern bumblebee, a species widespread in eastern North America, can withstand submersion for up to a week when hibernating.

With bumblebee queens known to burrow into soil to hibernate, the researchers say the phenomenon could help them survive flooding in the wild.

The team said its next priority was to explore whether the results hold for other species of bumblebee.

“We know that about a third of all bumblebee species are in decline currently [but] it’s not the case with [the common eastern bumblebee],” said Dr Sabrina Rondeau of the University of Guelph in Canada, adding the team was keen to learn whether flood tolerance could play a role in their resilience.

Rondeau and her co-author, Prof Nigel Raine, first made their discovery when a mishap in the laboratory led to water getting into containers in which hibernating queen bees were kept.

“After that, of course, curiosity led the way to conducting a full experiment with a lot of repetitions,” said Rondeau.

Writing in the journal Biology Letters, the scientists describe how they took 143 unmated, hibernating queens of the common eastern bumblebee and placed each in its own plastic tube containing damp topsoil. The tubes were then fitted with perforated lids and kept in a dark refrigerated unit for a week.

After checking the bees were still alive, the researchers kept 17 tubes as controls and added cold water to the remaining 126. While the queen was allowed to float on top of the water in half of these tubes, it was pushed under the water by a plunger in the others.

For both conditions, a third of the tubes were each left for eight hours, a third for 24 hours and a third for seven days, simulating different flooding conditions. The team subsequently transferred the bees to new tubes and monitored their survival.

The results reveal survival rates were similar regardless of the duration and conditions the queens had been subjected to – indeed 88% of the controls, and 81% of the queens that were submerged for a week, were still alive at eight weeks. However, queens with a higher weight had a greater chance of survival.

The researchers say the findings are unusual given most insects overwintering as adults – including many ground beetles – cannot cope with being submerged in water and must leave floodplains to survive.

While Rondeau said it was likely queens of other bumblebee species were also flood tolerant, ground nesting bees – which include some species of bumblebee – could still be affected by flooding as their larvae may not survive.

Among future areas of research, the team said it would be interesting to explore the mechanisms that underpin the queens’ resilience to flooding – with their low oxygen requirements during hibernation among possible important factors.

Prof Dave Goulson, a bee expert from the University of Sussex who was not involved in the work, said bee enthusiasts had long speculated that increased winter rain amid the climate crisis could drown many queen bumblebees as they hibernate underground.

“Amazingly, this new research shows that hibernating queen bumblebees are entirely unaffected by being held under water for up to one week,” he said. “This seems to be one small aspect of climate change that we need not worry about.”

It was a relatively cool spring day in Phoenix, Arizona, as a tree-planting crew dug large holes in one of the desert city’s hottest and least shaded neighborhoods.

Still, it was sweaty backbreaking work as they carefully positioned, watered and staked a 10ft tall Blue palo verde and Chilean mesquite in opposite corners of resident Ana Cordoba’s dusty unshaded backyard.

“If I ever retire, I’d like to be able to spend more time outside. The weather is changing, so I am really happy to get these trees. We need more shade,” said Cordoba, 75, a legal secretary, whose family has lived in Grant Park for more than a century.

Over the course of three days in early April, arborists planted 40 or so desert adapted trees in Grant Park, as part of the city’s equity-driven heat mitigation plan to create a shadier, more livable environment amid rising temperatures and hundreds of heat-related deaths.

Phoenix is America’s fifth largest and hottest city, a sprawling urban heat island which has expanded without adequate consideration to climate and environmental factors like water scarcity and extreme heat. ​Multiple heat records were broken last year including 133 days over 100F (37.7C), and 55 days topping 110F (43C).

Only around 9% of Phoenix is protected by tree canopies, yet this citywide figure masks vast inequities between wealthy, majority-white neighborhoods like Willo (13% coverage) just two miles north of Grant Park (4%). One census tract in the north-west of the city, Camelback East, has 23% tree cover.

“This is one of the city’s oldest neighborhoods – and one of the most neglected,” said Silverio Ontiveros, a retired police chief turned community organizer who drummed up interest for the tree planting by knocking on doors and putting flyers through every neighbor’s letterbox.

“Our goal is to change the inequity and create enough shade to provide residents and passersby reprieve from the heat. For that we need many more trees, but we also need to take care of them,” added Ontiveros, as he walked through the neighborhood making sure the right families got the right trees.

Grant Park is a majority Latino community in south Phoenix situated next to a sprawling electrical substation – a hot and dusty neighborhood with ​​200 or so homes, but no stores and plenty of empty lots and boarded-up houses. It was once a thriving neighborhood – one of the few places where people of color could live due to discriminatory housing policies that lasted most of the 20th century.

Redlined neighborhoods like Grant Park still have higher pollution levels, less vegetation, more noise pollution and higher temperatures. In recent years, the local outdoor pool was shuttered and scores of trees cut down by a previous administration to prevent homeless people from gathering in the shade.

“This is one of the hottest parts of the city because the people here don’t have political power,” said Leo Hernandez, 78, the master gardener at the thriving community garden where he created a butterfly sanctuary for migrating monarchs. “We need shade, but trees also suck up carbon dioxide, create places to socialize and healthier, happier neighborhoods.”

Trees have multiple benefits in urban areas which include cleaner air, improved physical and mental health, water conservation, increasing wildlife habitat, CO₂ storage and sequestration and lower temperatures through shade.

The city is mostly concerned with reducing the urban heat island effect and improving public health, and its 2010 shade masterplan set out a goal of achieving 25% citywide canopy cover by 2030. Amid little progress and rising heat mortality and morbidity, in 2021 Phoenix established the country’s first office of heat response and mitigation. Its community tree planting program is now being rolled out to public schools, churches and homes in qualifying census tracts – low-income neighborhoods with little shade.

Residents can choose from a list of 19 native and desert-adapted trees including the Texas olive, Chinese red pistache and Chilean mesquites. The trees, which are a couple of years old and pretty heavy, are planted by contracted arborists. For insurance reasons, they must be within the property – not the sidewalk – and not too close to walls or power lines. Each household also gets a tree kit – a 100ft hose, irrigation timer and instrument to measure the soil pH and moisture, as well as written care instructions.

This is the fourth tree-planting initiative in Grant Park, but the other schemes involved donations of smaller, younger trees which residents themselves had to plant in the dry, rocky earth. Several didn’t survive last summer’s heatwave when temperatures hit 100F (37.7C) on 31 consecutive days, while others died from overwatering or a lack of attention.

Tree planting has become increasingly popular among corporations, governments and environmental groups alike in recent years, with mixed results. In Turkey, 90% of the government’s 11m new trees died within months, while polluting industries including mining and fossil fuel companies have been accused of trying to greenwash environmental and climate harms.

“It is very hard to grow trees here, our environment is very extreme, so we’re doing everything we can to help them survive, which includes giving people the choice so they have species they love and feel excited about,” said Kayla Killoren, the heat office tree equity project coordinator. “There’s been a lot of greenwashing, and some people are weary and think it’s a scam at first, until they see their neighbors get trees planted.”

In Phoenix, a 75 to 80% survival rate would be considered a success, according to Killoren.

So far, 700 trees have been planted with scores more events planned throughout April and May, and will resume again in the fall after the summer heat. The project is mostly funded through non-profits, local and federal government grants including millions of dollars from the Covid stimulus package – the 2021 American Rescue Plan – and the Inflation Reduction Act.

There’s a long way to go and limited funds. According to American Forests, more than 800,000 more trees are needed to achieve 15% canopy cover for every residential block in the city.

The slow progress in improving tree coverage has frustrated many Phoenix residents, and in May, the heat team will present a new master shade plan to the city council, setting out more nuanced data-driven goals for homes, sidewalks and parks to replace the 25% citywide one. At the heart of the plan will be tackling shade inequalities that make rising temperatures increasingly deadly for the city’s most vulnerable communities, according to David Hondula, who leads the office of heat response and mitigation.

“The core concepts driving the masterplan are improving public health and livability by creating more shade in the places people spend most time,” said Hondula.

In Grant Park, the community celebrates every single tree but it will probably take years to create adequate shade to provide residents – including unsheltered neighbors and passersby – adequate protection from the worsening heat.

“We’ve always had to fight for everything here, we’re neglected but I love my neighborhood,” said Evangeline Muller, 75, who loads up her golf buggy with buckets to water the trees when it gets really hot. “Trees mean health, they give life, and I’m not going to stop fighting for my community.”