Saturday, 13 June 2009

Wool-Carder Bee watching 1: Male watching

The Wool-Carder Bee (Anthidium manicatum) is one of the most fascinating bees to watch in my garden. They are handsome bees, quite robust, with white-haired legs and brown hair on the body and stark yellow and black markings in the face and abdomen. Unlike most bees, Anthidium males are larger than females. The first Wool-Carder Bees appear in June. The males are territorial and defend a patch of flowers - frequented by females - with constant patrolling, and aggressively chase off or attack any intruders that pretend to 'steal' their nectar and pollen. It has been reported that they have killed other bees or bumblebees or rendered then unable to fly. Males have five pointed spines at the end of their abdomens with which they try and pierce other insects. The resident male flies when in patrol and hovers momentarily facing any possible insect, in most cases, the other bees flee when chased by the resident male. The males are most active in the middle of the day, resting on the early morning and late afternoon, often on a flower, holding on characteristically with his jaws. On this time, the other bees can forage in peace.
Male resting on Lavender
When the male notices a female in his territory he approaches and hovers behind her, waiting until she is feeding to jump on her and mate. Sometimes the male just approaches and seem to touch the female and leave her alone to feed.
Wool-Carder bees copulating on Lavender. In this photo the larger size of the male is obvious
Wool Carder bees have relatively long tongues (7.5-8.5 mm) and like deep flowers such as Lavender, Jerusalem Sage (Phlomis), Woundwort (Stachys), Tree Germander (Teucrium) and Sage (Salvia officinalis). Mating often takes place on these flowers.
Male feeding on Stachys byzantina or Lambs' ear
 Research by Severinghaus and coworkers on American populations has shown that male Wool-Carder bees follow two strategies to secure access to females. Larger males are territorial and mate with females feeding or gathering wool from their patch. Smaller males are 'wanderers' and sneak on resident male territories to mate with foraging females. This research, following marked bees on two summers, uncovered a remarkable level of turnover in territory ownership, with most territory ownerships lasting less than 4 days (the maximum was 30 days).
 In my garden, a male often rested on Jerusalem sage. Possibly the same male that ended up being a meal for a spider that lived on the same plant.
Male resting on Jerusalem Sage flower
Enoplognatha ovata has just captured the male

1 comment:

Rambling Rob said...

The presence of those spines at the end of the male's abdomen must make mating a more than usually delicate operation ?