Archive for the ‘Red on Abdomen’ Category

Vancouver bumble bee, Bombus vancouverensis

Wednesday, July 29th, 2020

Stop the presses! As of July 29, 2020 Washington state has a new bumble bee species. Genetic analysis has determined that the population of the Two form bumble bee, Bombus bifarius in British Columbia has been recognized as a new, separate species. This new species is the Vancouver bumble bee, Bombus vancouverensis. This includes the population located in the San Juan Islands. Ergo, we have a new species!

What is not clear is what the actual differences are between the Vancouver bumble bee and the Two form bumble bee. At first I (DJ) thought that the individuals showing red on T2 and T3 were vancouverensis and the ones with T2 and T3 black were bifarius. Now it appears separating the two species in Washington may be a bit more challenging. It appears that the two color morphs are subspecies of the same species (B. vancouverensis)

As I am interpreting (please correct me if you know better!) the colorful color morph found in the San Juans Islands is the Vancouver bumble bee subspecies Bombus vancouverensis vancouverensis, while the form that we knew in the eastern part of Washington as the Two Form Bumble bee (Bombus bifarius) is now the Vancouver bumble bee subspecies Bombus vancouverensis nearcticus. For more discussion on this taxonomic question, please refer to the Two Form bumble bee page.

For a more complete discussion on field identification of the Bombus vancouverensis nearcticus subspecies refer to the Two Form bumble bee page.

Field ID Tips

Range, range, range. As far as I am currently aware, within Washington state, the Vancouver bumble bee Bombus vancouverensis vancouverensis subspecies is restricted to the area around the San Juan Islands. It has a similar color pattern to the Two Form bumble bee. It shows an inverted black triangle on the scutellum. T1 & T4 are yellow. T2 and T3 show a lot of red. T2 may show a black notch.

Similar Species

The red morph of the Yellow head bumble bee, which is also located in the San Juans, is somewhat similar, but it show red on T3 and T4. The Yellow head bumble bee also lacks an inverted black triangle.

The Black tail bumble bee shows red in the middle of the abdomen. T4 is black with a white line of hairs, no inverted black triangle.

Frigid bumble bee, Bombus frigidus

Monday, July 27th, 2020


Field ID tips

The Frigid bumble bee, Bombus frigidus is a very rarely encountered bumble bee species in Washington. That may be because it is rarely looked for by individuals who go into the high country. That trend seems to be changing. I expect we will be adding additional locations to the map above. It has recently been detected at Harts Pass, by Rich Hatfield.

Key field marks are:

  • the yellow scutum and scutellum,
  • T1 & T2 yellow
  • T3 black (no white hairs)
  • T4 & T5 red/orange
  • high elevation

Similar Species

The Frigid bumble bee, Bombus frigidus is often found in association with two other high alpine specialists: the Forest bumble bee, Bombus sylvicola and the High country bumble bee, Bombus kirbiellus. All three show red on the abdomen.

The Frigid bumble bee, Bombus frigidus is easily distinguished from the Forest bumble bee because the red on a frigidus is at the end of the abdomen while the red on a sylvicola is on T2 and T3.

It is more of a challenge to visually separate the High country bumble bee from the Frigid bumble bee. They both have T1 and T2 yellow. The High country bumble bee, B. kirbiellus has black on the front half of T3, and yellow on the rear portion of T3. T4 and T5 are orange. Visually, this puts a break (yellow) between the black and red segments. This is in contrast with the Frigid bumble bee where black and red meet directly with no yellow line of separation.

Fuzzy-horned bumble bee, B. mixtus, and Sitka bumble bee, B. sitkensis are other similar species. A couple of key differences between kirbiellus and mixtus/sitkensis include:

  • Cloudy scutum on mixtus amd sitkensis /yellow on kirbiellus
  • Range (elevation)-one might find B. mixtus and sitkensis pretty high but you will not find frigidus in the lowlands

High country bumble bee, Bombus kirbiellus/balteatus

Monday, July 27th, 2020

As part of our quest to document all the bumble bee species found in Washington state the team of folks behind this website, David Jennings, Lisa Robinson and Don Rolfs established a state record for the High country bumble bee, Bombus kirbiellus.

In the summer of 2018 David organized an expedition to one of Washington’s high alpine regions, Horseshoe Pass. While in the high country Don netted and collected a bumble bee. We could not easily confirm it’s identity in the field, so it was collected. That bee was subsequently mounted and identified by Lisa. She keyed it out to be Bombus kirbiellus, better known as the High country bumble bee. Until we made this find, there had been no verifiable evidence of this species in Washington state.

Lisa reached out to Rich Hatfield, of the Xerces Society and he helped get our suspicions confirmed by having her identification collaborated by Dr. Paul H Williams at the Natural History Museum, London UK, a worldwide expert on the species.

Teamwork for the win!

Last year (2019), based on our finding, Rich Hatfield visited the site and wrote up his findings here: https://www.xerces.org/blog/bombus-kirbiellus . That would have been a fun trip to be on!

And in reading his article I learned something very useful! The preferred food plant of kirbiellus. Red paintbrush is an easy flower to spot on the landscape!

Again, teamwork for the win!

Field ID tips

The High county bumble bee, Bombus kirbiellus, is as the name suggests a high elevation specialist. There are only a few places high enough with enough resources available for kirbiellus in Washington. The species is much more common in the high alpine country of Colorado up into Montana.

The scutum and scutellum are both yellow, with a black band between the wings. T1 and T2 are yellow, T3 is black with some white hairs in a line, T4 and T5 show orange or red.

Similar Species

The High country bumble bee may be found in association with two other high alpine specialists: Forest bumble bee, Bombus sylvicola and the Frigid bumble bee, Bombus frigidus. All three show red on the abdomen.

The High country bumble bee is easily distinguished from the Forest bumble bee because the red on a kirbiellus is at the end of the abdomen while the red on a sylvicola is on T2 and T3.

It is more of a challenge to visually separate the High country bumble bee from the Frigid bumble bee. They have T1 and T2 yellow. B. kirbiellus has black on the front half of T3, and some yellow on the rear portion of T3. T4 and T5 are orange. Visually, this puts a break (yellow) between the black and red segments. This is in contrast with the Frigid bumble bee where black and red meet directly with no yellow line of separation.

Fuzzy-horned bumble bee, B. mixtus, is another similar species. A couple of key differences between kirbiellus and mixtus include:

  • Cloudy anterior thorax (scutum) on mixtus/yellow on kirbiellus
  • No yellow break between black and red on lower abdomen (mixtus)

As can be seen below, the front of the thorax is yellow, not cloudy. T1 and T2 are yellow. There is a narrow yellow band breaking up the black/red interface on lower tergites.

Bumbles with Red on abdomen

Friday, July 24th, 2020

This group is fairly large.

To reduce the number of species to compare against, Bumbles with RED are divided into two subcategories:

Bumbles with red on the middle of their abdomen,

OR

Bumbles with red at the hind end of their abdomen

Look at your bee: where does the red occur? Based on what you find, go to the subgroup page to sort throw likely options.

Sitka bumble bee, Bombus sitkensis

Sunday, July 19th, 2020

Field ID tips

The thorax area in front of the wings (anterior thorax) is cloudy-a mixture of yellow and black hairs. The rear of the thorax (scutellum) is black. It may show some yellow on the sides as in the picture above.

The two front segments of the abdomen (T1, T2) are yellow. T3 is black. The end of the abdomen (rear of T4, T5, T6) has faint orange/pale hairs.

Similar Species

Two species that should be ruled out are Yellow head bumble bee, B. flavifrons and Fuzzy-horned bumble bee, B. mixtus. In the first instance, the pale hairs at the end of the tail can be missed (flavifrons). In the second, the red/pale hairs of sitkensis are not as prominent as exhibited by most B. mixtus. Mixtus may also show orange on T3.

As seen in the picture above, the anterior thorax is cloudy, T1 and T2 are yellow. T3 is black. T4 may show lots of black also, but will also have pale hairs. The pale hairs on T5 at the end of the abdomen are also visible.

Forest bumble bee, Bombus sylvicola

Sunday, July 19th, 2020

The Forest bumble bee, Bombus sylvicola is a high altitude specialist. Here in Washington it is only found in the lofty elevations in the Olympics and Cascades. In a study done for the National Park Service, Bombus sylvicola, occurred only at sites between 1,113 and 2,023 meters in both parks.

The Forest bumble bee, Bombus sylvicola may be found in association with one or two other high alpine specialists: Frigid bumble bee, Bombus frigidus and the High country bumble bee, Bombus kirbiellus. All three show red on the abdomen. The Forest bumble bee appears to be the most common of the three species here in Washington state.

A general characteristic across these high altitude specialists relative to bumbles from lower elevations is long hair length. For this species, this would be relative to the Hunt bumble bee, Bombus huntii.

Field ID tips

First, this is one species where range is a prime consideration. Unless you are pretty high in the mountains, don’t expect to encounter the Forest bumble bee. The Forest bumble bee has a yellow scutum and scutellum, and T2 & T3 are red.

Similar species

The Forest bumble bee is easily distinguished from the Frigid bumble bee and the High Country bumble bee because the red on a frigidus and a kirbiellus is at the end of their abdomen while the red on a sylvicola is on T2 and T3. The same logic holds true for separating the Forest bumble bee from the Fuzzy-horned bumble bee, B. mixtus and the Sitka bumble bee, B. sitkensis.

The Forest bumble bee, B. sylvicola, has a color pattern similar to the Hunt bumble bee, B. huntii. They both have T1 yellow, T2 and T3 orange, T4 yellow. Luckily these two species can easily be separated based on range. The Forest bumble bee is a high alpine specialist while the Hunt bumble is comfortable in hot dry sites like the Dry Falls State Park lake basin.

The scutum is yellow in sylvicola. This can help distinguish between sylvicola and melanopygus, the Black tail bumble bee. The Black tail bumble has a cloudy scutum (black hairs mixed in with the yellow).

The Red-belted bumble bee, B. rufocinctus, has the potential to be confused with the Forest bumble bee. The Red-belted bumble bee shows T2 with some yellow. The Forest bumble bee has T2 all red.

To date, I (DJ) have not captured any images of sylvicola in Washington. The quest continues…

Hunt bumble bee, Bombus huntii

Saturday, July 18th, 2020

The Hunt bumble bee, Bombus huntii, is in my book one of the most spectacular bumbles we have in Washington. Their colors can be so brilliant. Once you encounter and identify this species, you will rarely have difficult identifying other such individuals.

Field ID tips

At the photographic detail level, the field marks that distinguish the Hunt bumble bee, B. huntii are

Again, once you encounter one I doubt you will find them confusing to separate from other species. Sometimes the colors are faded on a older individual (check wing condition for an estimate of age) so the patterns of color need to be noted.

Similar Species

The main species in Washington with a similar color pattern is the Forest bumble bee, Bombus sylvicola. Key differences between the two species are first: range. The Forest bumble bee is a high altitude specialist while the Hunt bumble is a lowland dry country specialist. Think Dry Falls State Park. The second key difference is on T5. The T5 on a female Hunt bumble bee is all black. The T5 on a Forest bumble will show yellow, possibly with a black notch.

Based on where the majority of the detections are in the map above, the Hunt bumble bee is very much a dry country / east side species.

T1 = yellow, T2, T3 = orange, T4 = yellow, T5 black. The abdominal segments are relatively easy to count off in these pictures.

Fuzzy-horned bumble bee, Bombus mixtus

Saturday, July 18th, 2020

I find the Fuzzy-horned bumble bee, Bombus mixtus, to be a common species in Thurston County and much of the west side. It is also found in the north central of the state, and the mountainous areas in eastern Washington.

Please reference the Embedded Range Maps page to better interpret
# of observations per ecoregion.

Field ID tips

The relatively bright red rear of the abdomen is a prominent field mark I see on this species. The abdomen feels three (3) toned. Yellow transitioning into black and then into orange.

  • T1 = yellow
  • T2 = yellow with some/ a lot of black possible
  • T3 = black, possibly with some orange
  • T4 = orange
  • T5 = orange

Similar Species

My ID challenge with the Fuzzy-horned bumble bee, B. mixtus is that there are some other, less common species with similar color patterns, such as the Sikta bumble bee, the High country bumble bee and the Frigid bumble bee. Recognizing that an individual with red at the end of the abdomen is NOT mixtus is the larger challenge.

Let me restate: assume you are looking at a Fuzzy-horned bumble bee and then decide if one of the other species may be a better match.

Having said that, Sitka can be ruled out easily because the colors at the end of the abdomen are not as bright and often do not extend up to T3 or even the front portion of T4.

The other two are easily ruled out in most circumstances based on location. Those two species, are high alpine specialists and are not routinely encountered unless extremely lucky or on a targeted mission. A key field mark for separating Bombus mixtus from the other two is color of the scutum. The Fuzzy-horned bumble bee has a cloudy scutum (yellow with black hairs also). The scutum on both the High country bumble bee and the Frigid bumble bee is yellow.

Black tail bumble bee, Bombus melanopygus

Friday, July 17th, 2020

The Black tail bumble bee, Bombus melanopygus, can be encountered in many areas around Washington state: Lowlands like Tumwater on the west side, in the mountains and over across the top of the state and beyond.

When I first started taking pictures of bumbles this species was one of the first I submitted to Bumble Bee Watch. It was also the species that taught me the bumble bee term “cloudy“. Cloudy is the term to describe bumble patterns that have a mixture of black and yellow hairs. On the Black tail bumble bee, the area in front of the wings (scutum) and behind the head is such a mixture of black and yellow. And on the Black tail bumble that cloudiness is very obvious.

Field ID tips

Abdomen pattern is similar in many respects to the Hunt bumble bee, with the big difference at T4.

The Black tail bumble bee

  • Anterior thorax = cloudy (area in front of wings)
  • T1 = yellow
  • T2 = orange
  • T3 = orange
  • T4 = black with some white hairs
  • T5 = black

T4 is black with some white hairs rather than cloudy because the white hairs are in a distinctive line rather than mixed in among the black hairs.

Similar Species

Species that could cause confusion include:

My experience has been that the Black tail bumble bee is pretty distinctive most of the time, leading to confident field identification.

Central bumble bee, Bombus centralis

Friday, July 17th, 2020

Within Washington state, this species is most clearly an east side one. While there may be a sighting or two on the west side, over on the east side it can be relatively common.

This species clearly shows red on the abdomen. What makes it easy to separate from all others is that the red is on tergites T3 and T4.

  • T1= yellow
  • T2 = yellow
  • T3 = orange
  • T4 = orange
  • T5 = black

Within eastern Washington, there are few other species that one might confuse with the Central bumble bee. One possibility would be if you encountered a reddish form of Yellow head bumble bee, B. flavifrons.

The red forms of B. flavifrons have a cloudy front thorax. The Central bumble bee has a yellow one.