European Red List of Bees

features explain this pattern across Europe: (i) the more
favourable energy/water balance of the Mediterranean
areas which has resulted in extremely high floral diversity
(Patiny et al. 2009); and (ii) the likely role of these areas
as refuges during the Quaternary glaciations (Reinig
1937, De Lattin 1967).
There are 400 species (20.4%) that are endemic to Europe
and 277 species (14.6%) that are endemic to the EU 27
(see Table 1). At the European level, the family with the
highest percentage of endemism is the Melittidae with
35.1%, and the family with the lowest endemicity are the
Megachilidae with only 16.7% (Table 1). At the EU 27
level, the family with the highest percentage of endemism
is the Colletidae with 21% and the family with the lowest
endemicity are the Apidae and the Megachilidae with
13.5% (Table 1).
Many of the European endemic species are
predominantly found on restricted montane habitats
(Alps: Osmia steinmanni Müller 2002; Sierra Nevada:
Bombus reinigiellus Rasmont 1983), islands such as the
Canary Islands (e.g., Melecta canariensis Hohmann et al.
1993), and the Mediterranean islands of the Balearics
(Anthophora balearica Friese 1896), Corsica (e.g., Bombus
pereziellus Rasmont and Adamski 1996), Crete (e.g.,
Ceratina teunisseni Terzo and Rasmont 1997), Cyprus
(e.g., Chelostoma comosum Müller 2012), and Sicily (e.g.,
Chelostoma siciliae Müller 2012). The Mediterranean
peninsulas of Spain, Italy and Greece also show a higher
percentage of endemic species.
1.3 Bee ecology
Bee ecology can be characterised based on food, sociality
and nesting requirements.
Bees can collect various resources from plants such as
pollen, nectar, and less commonly, oil or perfumes; some
materials used for nesting like resin, soil, and pieces of
leaves and petals are also collected (Wcilso and Cane
1996, Michener 2007). Various foraging strategies have
been described for bees mainly based upon the range of
pollen collection from host plant(s). Bees collect pollen
as a food source for their larvae and, in doing so, help
pollinate the flowers of the plants upon which they forage.
Some taxa display floral specificity, restricting their flower
visits to closely related plant taxa (pollen specialists) while
other bee species are more opportunistic, exploiting a wide
range of different flowers (pollen generalists) (Dötterl and
Vereecken 2010). Terms have been developed to describe
the continuum in bee foraging strategies, from extreme
specialisation to extreme generalisation: (i) monolecty (one
host plant species); (ii) oligolecty (one host plant family)
and (iii) polylecty (more than one host-plant family) (Cane
and Sipes 2006, Müller and Kuhlmann 2008). Moreover,
quantitative pollen requirement is relatively high for bees
as they forage only on pollen for protein resources while
other pollinators like syrphid flies or butterflies feed on
alternative resources in the larval stage. Depending on
both bee species and plant resources, from seven to 1,100
flowers or from 0.9 to 4.5 inflorescences are needed to rear
a single larva (Müller et al. 2006).
Table 1. Diversity and endemism in bee families in Europe*.
Europe EU 27
Class Order Family
Number of
species
Number of
endemic species
(% endemic)
Number of
species
Number of
endemic species
(% endemic)
Insecta Hymenoptera Andrenidae 465 96 (20.6%) 443 62 (14%)
Apidae 561 107 (19.1%) 535 72 (13.5%)
Colletidae 146 40 (27.4%) 143 30 (21%)
Halictidae 314 70 (22.3%) 306 47 (15.4%)
Megachilidae 442 74 (16.7%) 436 59 (13.5%)
Melittidae 37 13 (35.1%) 37 7 (18.9%)
Total 1,965 400 (20.4%) 1,900 277 (14.6%)
* This table includes species that were native or naturalised since before AD 1500; species introduced after this date are not included. Species of marginal
occurrence in Europe or the EU 27 are included. For the EU 27 level assessment the Not Evaluated species (species which do not occur in the EU and that
represent a total of 65 species) are excluded.
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