Hi David,

I think that don’t have a coevolution between some kinds of trees and nests of a hummingbird species, but I think that some kinds of trees can offers more frequently the microhabitats required by some hummingbirds. For example, Glaucis hirsutus nests can be found in very kinds of palms, because your nest type requires a microhabitat easily made by leafs of palm tree, but other trees can be eventually offer similar conditions, but it don’t frequently found because are very small.

This is my opinion and I think that can be a good question to be answered!

Hi David,

The Barred Warbler (Sylvia nisoria) has a tendency to breed in thorny bushes. Since the Barred Warbler is in a sympatric breedings ass. with the Red-backed Shrike (Lanius collurio) also this second species prefers thorny bushes.

Results from a study in Poland suggest that the Red-backed Shrike has a higher fidelity to a single species of bush than the Barred Warbler but might be worth looking at (Link: http://www.sekj.org/PDF/anz49-free/anz49-355.pdf )

The reason why both these species choose to breed in a thorny bush is to be protected from predators (no official source for this!), but I do know that the Shrike sometimes uses these thorns to "mount" a piece of prey to, to make it easier to pull apart the preyitem, or just to store it for a while!

Anyway, just like Gabriel mentioned, good question to be answered!

As explained by Micha above, the Red-backed shrikes use to build the nest mainly thorny shrubs. In several countries of Europe, the main shrubs used are Prunus spinosa, Rosa canina or Paliurus spina-christi... but also other ones.

The reason are mainly two (always as highlighted by Micha): protection of nesting habitat (thorns) and coverage, but also as good sites where to place the preys (the larders of Lanidae are well known), because Red-backed shrike, like a little raptor, hunt and capture the prey, but as they haven't claws, need a mechanic support to snatch the corpses, to be eat.

Look some our studies.... with examples of the first case and the second case...

https://www.researchgate.net/publication/236897060_First_description_of_red-backed_shrike_Lanius_collurio_food_caching_in_Central_Italy_preys_type_and_spatial_position_into_the_larders?ev=prf_pub

https://www.researchgate.net/publication/230793566_PLASTICITY_OF_HABITAT_SELECTION_BY_RED-BACKED_SHRIKES_(LANIUS_COLLURIO)_BREEDING_IN_DIFFERENT_LANDSCAPES?ev=pub_cit

Good luck!

Federico

Article First description of red-backed shrike Lanius collurio food ...

Article Plasticity of Habitat Selection By Red-Backed Shrikes (Laniu...

Thank you for the additional info. Actually also good for me to have a look a the two articles you suggested! :)

Micha