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    Inside the Mason Bee Nest

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  • Bright orange pollen in Observation nest-update


    An interesting observation from Diane.

    “This morning I peaked into small observation nest purchased some years ago
     and noted a bright red color on top surface of one edge of two
    cells…do you know what this might be?

    Ohh how lovely.  The bee has collected pollen from two sources, one flower
    with yellow pollen and the other flower with orange pollen.

    By touching the anthers of flowers you can see there is quite a lot of
    pollen colors out there.  One flower that has bright orange pollen is theTiger lily.



    This is a picture of a 3 nesting tunnel observation/viewing nest.  The lowest tunnel is empty.  The middle tunnel contains 3 completed chambers with pale yellow pollen.  Two cells ( of the four) in the upper channel have bright orange and yellow pollen as part of the pollen lump.  There is even a bee in the upper nesting tunnel.
     Thanks so much…another bit of learning…this is fun!   Diane
    Here is a picture of the same nest taken about a month later. 
    Cocoons are fully formed  with adult bees inside.
  • Inside the nest- healthy cocoons and mites

    Here is Frank’s third photo. 

    “015 shows channels with healthy cocoons, but I’ve never seen so much bee frass!!  The only part of the cocoons visible in the image is where the cocoon surfaces were tight against the base of the overlying tray. Othewise all the free space around the cocoons is packed with frass.  Have you ever seen the likes of it?”
    The Dutch would describe the frass to look like a sandwich spread called Chocolate Hail!  Not as yummy though.
    I have on occasion seen frass in these quantities.  I think it means that these bee larvae were well fed and then produced lots of frass or bee feces.  These healthy bees will have the energy to eat their way out of their cocoon and start a successful nest.
    Another interesting item  in this photos is those tiny pale blond spots all over the wood and over the cocoons.  These are the pollen feeding mites.  If these mites are not removed, mites wait for the bee to open the cocoon, the mite sneaks in and attaches itself to the bee- to set up house in the next nest.
  • Inside the nest-pupae and wiry frass

    Here is Frank’s photo number 017 
    It shows a wooden tray infested with foreign larvae, plus at least four different-looking types of wiry frass.  Are they all from the same insect and  reflect differences in diet, or might they actually represent different organisms?”
    The upper channel possibly contains the pupae of the houdini fly.  The lower channel has 3 chambers with wiry frass that probably belongs to the spider beetle.
    Lovely photos Frank.  Sorry we could not be more clear on the ID of these insects.  Let me know if you have placed them in a petri dish to develop into full adult.
  • Inside the nest- many white pupae

    Here is photo 011 by Frank M. 
    Frank writes “011 shows just how abundant these foreign larvae were in some cases.  In this image, they are actually spilling out of the channels because the upper part of the channel was filled too. Notice also that at the right-hand side of the image there is a chamber filled with wiry frass that is different from the stuff in image 004.”

    These grubs, may well be the ‘fruit fly’ Joe S. took and I wrote about on Jan 7th 2011 in this blog.  Joe mentioned these fruit flies had red eyes.  A friend of Joe’s searched the web and came up with “houdini fly”  Cacoxenup-inbagator flies.

    If you still have these grubs, set them up in a moist warm environment such as a petri dish and see what comes out.  What an interesting project for a child who is interested in science.  The search continues.

  • Inside the nest- wiry frass

    Frank M.  contacted me recently about his findings at his yearly mason bee workshop.  A most interesting series of photos- with permission.

    “This photo shows some extraordinary wiry frass, even more wiry than the material that I showed you last year from the 2010 harvest.  Any ideas?  There is also some fluffy stuff in the same chamber and the one next to it, similar to the material in one of the images on one of your blogs.”
    This beautifully constructed chamber inside a routered piece of wood, has concave mud walls.  It normally contains one masn bee cocoon, but something has entered it.  The chamber contains frass- or insect fecal material.  According to Bosch and Kemp (2009)  wiry frass is likely produced by one of two insects found in masn bee nesting tunnels.  One is the cuckoo bee.  If there is a cocoon amongst the mass of frass- then it would be the cuckoo bee.  If there is no cocoon- it is most likely the spider beetle.  It is about 2-3mm long with 4 white patches on its back and long attennae.  Both insects eat and destroy the mason bee larvae and its food.  They both invade the chamber when it is pretty close to being sealed by the bee.
  • Inside the nest: cocoons inside ‘cotton fluff”

    There have been half a dozen reports of cotton fluff inside the nesting tunnels.  Here is one I found myself.  Most of the fluff is just that, but two cocoon type structures were found in the center row.  If someone knows what this is please let us know.

    A nesting tray with 6 routered channels containing mason bee cocoons,
    and cotton type fluff in two of the channels.
    Here I have lifted some of the fluff out to show how it neatly fits into the channel.
    Two cocoons were found inside this fluffy material.
    You can see the end cap directly above where the cocoon is held in the photo.
    The end cap is made of several layers of mud and is thicker than the usual mason bee end cap.
    For comparison, this appears like a spider web,
    which either contains young spiders or an adult spider.
  • Inside the nest- Resin bees

     When I find resin bees inside nesting tunnels, I remove any mason bee cocoons , remove mason bee debris out of tunnels with a tooth brush, close up the nest and set out side ready for next year.

    Two delicately placed resin walls.  No bees were in these cells.

    Resin bee pupae within compartments made of resin.

    Last year’s resin bees emerged during summer months
    when resin softened up with the heat.   

  • Inside the nest:Beneficial wasps

    Here the beneficial wasp is inside a routered tray nesting tunnel,
     securely within its mud vestibule.
    TODO:  Remove any mason bee cocoons with a Scoop and  remove
    debris with an old toothbrush.  Then replace lid over beneficial wasps and  set
    outside ready for next year.

  • Inside nests: Mix of cocoon types and wasp pupae

    Last week a mason bee keeper asked me to look at these two photos and give them feedback on the insects inside the nesting tunnels.  Every nesting tunnel tells a story!

    These are beneficial wasp pupae encased in a very delicate cover.  They provision their nests with either spiders,
    aphids or moth larvae.  Sometimes if an egg does not
    develop the larvae food remains in the cell.
    This is a picture of cocoons harvested from nesting tunnels.
    The dark brown, still with mud attached, is from the early
    spring mason bee Osmia lignaria.  The reddish cocoon with its bright
    orange fecal material and masticated leaf plugs are probably
    Osmia californica.  Osmia californica is active towards the end of the
    early spring mason bee activity.
  • What do mason bee cocoons look like inside the nest?

    These cocoons were harvested early October just when weather was getting colder
    and water was condensing on the Quicklock nesting trays.
    Early enough to  avoid fungal growth over cocoons.

    These cocoons were harvested in early Nov, after cold weather had settled in.
    A few cocoons were covered in mold.  This mold is easily washed off in cold water and a little bleach.
    Quicklock nesting trays with 4 healthy looking cocoons.
    Cocoons are covered in feces which is easily washed off in cold water.
    Quicklock trays with healthy cocoons.  The brown and black speckles
    are bee feces or frass.
    Frass is easily washed off in cold water.

    These are different coloured mason bee mud plugs in Quicklock nesting trays.
    The black paint is used to help bees orient to their nesting tunnel.

    Small cocoons towards the front of the tunnel are usually males.
    The females are in the back of the nesting tunnel and are larger than the male cocoon.
    Sometimes a nesting tunnel consists of a few mud debris.
    The female either died before she could finish the nest or she  became
     disoriented and found another nesting tunnel for nesting.
    Tunnels can be completely full or partly filled.