Species at Risk Updates: Red-necked Phalarope and Yellow-banded Bumblebee

At its January meetings, Dawn Andrews from the Canadian Wildlife Service updated the Board on proposed species at risk listings for two wildlife species:  the Red-necked Phalarope and the Yellow-banded Bumblebee.  Both species are being proposed for listing as species of Special Concern under the federal Species at Risk Act.  When a species is listed as a species of Special Concern, a management plan is prepared to outline measures to ensure that the species does not become threatened or endangered. 

The Red-necked Phalarope

This small, delicately-shaped shorebird breeds in low and sub-Arctic wetlands and forest-tundra transition areas throughout the NWT, including Wek’èezhìı. It winters at sea off the coast of Persu, and spends the summer in the North, arriving in the NWT from late May to early June.  On their journeys north, Red-necked Phalaropes stop at inland lakes and ponds with abundant aquatic insects and other invertebrates to feed on. Once they reach their breeding grounds, they nest mainly on the marshy edges of ponds, lakes and streams. 

Their populations are difficult to monitor, but declines have been noted on breeding grounds in northern Manitoba and the Yukon and in important staging areas, places where the birds stop to rest and feed during their migrations.  Particularly concerning is the sharp drop in their numbers in the western Bay of Fundy.  Fall gatherings there had been estimated as high as 3 million in the 1970s, but numbers began to drop sharply in the 1980s and those large concentrations of birds have mostly disappeared.   

What factors may be affecting these birds and the habitats they depend on?  In the NWT, a potential threat is loss and degradation of their summer breeding habitat.  The effects of climate change, including the drying of freshwater ponds and the expansion of shrubs into the tundra wetlands, may be affecting habitat quality and availability.  As well, the removal of vegetation caused by increasing Snow Geese populations is also likely to have negative effects on these birds and their breeding habitat. 

During other times of the year when they’re not breeding, there may be other threats facing Red-necked Phalaropes.  They spend most of the year on the open ocean.  Changes in ocean temperatures, salinity (the amount of salt dissolved in the water) and currents due to climate change –as well as declines in available prey at traditional staging areas and over-wintering sites are likely factors. Red-necked Phalaropes are also susceptible to oil spills and other pollutants while at sea when the birds gather in large numbers on the ocean.  As well, they may accidently ingest microplastics (tiny pieces of plastic debris on beaches and in coastal waters) or experience disturbances from shipping traffic or other sources. 

Fact Box

•  Red-necked Phalaropes have an interesting feeding behaviour. They forage mostly by swimming, by picking items such as plankton from the water’s surface or just below it. Often, they will spin in circles on the shallow water.  It’s thought that they do this to stir things up and bring food closer to the surface.  On the open ocean, Red-necked Phalaropes will often gather over upwellings where cold nutrient-rich water rises to the surface.  There the water brings with it the zooplankton (microscopic animals) that these birds feed on. 
• Unlike many other kinds of birds, the females are more brightly coloured than the males.  And in another role reversal, it’s the males who undertake most of the parental care, looking after the eggs and tending to the young. 
• Microplastics can pose physical and chemical hazards to wildlife.  They are easily ingested by fish, seabirds or other wildlife.  Toxins may adhere to the particles and then enter the food chain. 

The Yellow-banded Bumblebee

Recent research has shown sharp declines in some bumblebee species, including the Yellow-banded Bumblebee.  Historically, the Yellow-banded Bumblebee was one of the most common bumblebee species in Canada within its range.    It appears relatively abundant in the northern and western part of its range, including parts of Wek’èezhìı and across the NWT--but studies since the 1990s suggest that there have been significant population declines across south and central Canada.

In the NWT, these bumblebees tend to be found in taiga habitat next to wooded areas, foraging for pollen and nectar from a variety of flowers. 

There are a number of threats which may be leading to the decline of the Yellow-banded bumblebee.  Significant threats include:

• Habitat loss or change.  Bumblebees need a suitable underground area for nesting, such as abandoned rodent burrows, or above ground in old logs or under grass mounds.  They need places to overwinter, often in rotting logs or decomposing leaves and other vegetation, and they need an abundance of wildflowers for food from spring through fall.  All three types of habitat may be threatened by agricultural and urban development, and other changes to the landscape which result in a shortage of flowers to feed from and places to nest.    
• The spread of pathogens from bees in greenhouses.    The use of bees for pollination of greenhouse crops can spread disease from managed to wild bumblebees.  Bees in commercial bee hives may have a number of pathogens not present in the natural environment.  When they ‘escape’, they may intermingle with native bumblebees foraging nearby and introduce diseases not seen in the area. 
• Pesticide use.  Pesticides may have harmful effects on bumblebees as they forage from treated plants as well as untreated plants.  Pesticides may also indirectly harm bumblebees by removing the flowers that would otherwise provide the bees with pollen and nectar. 
• Climate change.  Bumblebees are adapted to the cold and may be affected by long-term changes in weather patterns. 

Fact Box

• These bumblebees are very selective about the flowers they pollinate.  Apparently they can determine the quality of pollen in a flower from a distance, but how they do this is not yet known. 
• A new queen is born in late summer. Only the new, mated queens overwinter; the old queen, males and worker bees all die at the onset of the first frost.
• One of the earliest bumblebees to emerge in spring, the young queen begins searching for suitable nesting sites and collects nectar and pollen to support the production of her eggs.