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The forgotten flies: the importance of non-syrphid Diptera as pollinators.

Orford KA, Vaughan IP, Memmott J - Proc. Biol. Sci. (2015)

Bottom Line: We found no significant difference in pollen-loads between the syrphid and non-syrphid Diptera.Moreover, there was no significant difference in the level of specialization between the two groups in the pollen-transport networks, though the Syrphidae had significantly greater visitation evenness.Flower visitation data from 33 farms showed that non-syrphid Diptera made up the majority of the flower-visiting Diptera in the agricultural studies (on average 82% abundance and 73% species richness), and we estimate that non-syrphid Diptera carry 84% of total pollen carried by farmland Diptera.

View Article: PubMed Central - PubMed

Affiliation: School of Biological Sciences, University of Bristol, Bristol Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK katy.orford@bristol.ac.uk.

ABSTRACT
Bees, hoverflies and butterflies are taxa frequently studied as pollinators in agricultural and conservation contexts. Although there are many records of non-syrphid Diptera visiting flowers, they are generally not regarded as important pollinators. We use data from 30 pollen-transport networks and 71 pollinator-visitation networks to compare the importance of various flower-visiting taxa as pollen-vectors. We specifically compare non-syrphid Diptera and Syrphidae to determine whether neglect of the former in the literature is justified. We found no significant difference in pollen-loads between the syrphid and non-syrphid Diptera. Moreover, there was no significant difference in the level of specialization between the two groups in the pollen-transport networks, though the Syrphidae had significantly greater visitation evenness. Flower visitation data from 33 farms showed that non-syrphid Diptera made up the majority of the flower-visiting Diptera in the agricultural studies (on average 82% abundance and 73% species richness), and we estimate that non-syrphid Diptera carry 84% of total pollen carried by farmland Diptera. As important pollinators, such as bees, have suffered serious declines, it would be prudent to improve our understanding of the role of non-syrphid Diptera as pollinators.

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Related in: MedlinePlus

Absolute differences in (a) total abundance and(b) species richness between the Syrphidae andnon-syrphid Diptera found on each of the 33 farms (each barrepresents a farm). Positive values show higher abundance or speciesrichness of the non-syrphid Diptera than the Syrphidae.
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RSPB20142934F2: Absolute differences in (a) total abundance and(b) species richness between the Syrphidae andnon-syrphid Diptera found on each of the 33 farms (each barrepresents a farm). Positive values show higher abundance or speciesrichness of the non-syrphid Diptera than the Syrphidae.

Mentions: Non-syrphid Diptera were significantly more abundant than the Syrphidae inagricultural habitats; a median of 28 and six insects were recorded per farmrespectively (χ2 = 24.29, d.f.= 1, p < 0.001, R2m= 0.21, R2c = 0.83; figure 2; electronicsupplementary material, table S2). On average, the non-syrphid Diptera made up82% (s = 23%) of the dipteran abundancerecorded on the farms. Species richness of non-syrphid Diptera was also higherthan the Syrphidae; a median of seven and three species per farm, respectively(χ2 = 27.08, d.f. = 1,p < 0.001, R2m =0.15, R2c = 0.88; figure 2; electronic supplementary material,table S2). On average non-syrphid Diptera made up 73% (s= 19%) of dipteran species. Following rarefaction, the speciesrichness of the non-syrphid Diptera was still greater than the Syrphidae(χ2 = 23.27, d.f. = 1,p < 0.001, R2m =0.055, R2c = 0.94); therefore, patternsdetected were unlikely to be driven by sampling effects. Together the dipterangroups made up 67% of the total abundance and 66% of the totalspecies richness of all flower-visitors in the farm networks. Figure 2.


The forgotten flies: the importance of non-syrphid Diptera as pollinators.

Orford KA, Vaughan IP, Memmott J - Proc. Biol. Sci. (2015)

Absolute differences in (a) total abundance and(b) species richness between the Syrphidae andnon-syrphid Diptera found on each of the 33 farms (each barrepresents a farm). Positive values show higher abundance or speciesrichness of the non-syrphid Diptera than the Syrphidae.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4389612&req=5

RSPB20142934F2: Absolute differences in (a) total abundance and(b) species richness between the Syrphidae andnon-syrphid Diptera found on each of the 33 farms (each barrepresents a farm). Positive values show higher abundance or speciesrichness of the non-syrphid Diptera than the Syrphidae.
Mentions: Non-syrphid Diptera were significantly more abundant than the Syrphidae inagricultural habitats; a median of 28 and six insects were recorded per farmrespectively (χ2 = 24.29, d.f.= 1, p < 0.001, R2m= 0.21, R2c = 0.83; figure 2; electronicsupplementary material, table S2). On average, the non-syrphid Diptera made up82% (s = 23%) of the dipteran abundancerecorded on the farms. Species richness of non-syrphid Diptera was also higherthan the Syrphidae; a median of seven and three species per farm, respectively(χ2 = 27.08, d.f. = 1,p < 0.001, R2m =0.15, R2c = 0.88; figure 2; electronic supplementary material,table S2). On average non-syrphid Diptera made up 73% (s= 19%) of dipteran species. Following rarefaction, the speciesrichness of the non-syrphid Diptera was still greater than the Syrphidae(χ2 = 23.27, d.f. = 1,p < 0.001, R2m =0.055, R2c = 0.94); therefore, patternsdetected were unlikely to be driven by sampling effects. Together the dipterangroups made up 67% of the total abundance and 66% of the totalspecies richness of all flower-visitors in the farm networks. Figure 2.

Bottom Line: We found no significant difference in pollen-loads between the syrphid and non-syrphid Diptera.Moreover, there was no significant difference in the level of specialization between the two groups in the pollen-transport networks, though the Syrphidae had significantly greater visitation evenness.Flower visitation data from 33 farms showed that non-syrphid Diptera made up the majority of the flower-visiting Diptera in the agricultural studies (on average 82% abundance and 73% species richness), and we estimate that non-syrphid Diptera carry 84% of total pollen carried by farmland Diptera.

View Article: PubMed Central - PubMed

Affiliation: School of Biological Sciences, University of Bristol, Bristol Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK katy.orford@bristol.ac.uk.

ABSTRACT
Bees, hoverflies and butterflies are taxa frequently studied as pollinators in agricultural and conservation contexts. Although there are many records of non-syrphid Diptera visiting flowers, they are generally not regarded as important pollinators. We use data from 30 pollen-transport networks and 71 pollinator-visitation networks to compare the importance of various flower-visiting taxa as pollen-vectors. We specifically compare non-syrphid Diptera and Syrphidae to determine whether neglect of the former in the literature is justified. We found no significant difference in pollen-loads between the syrphid and non-syrphid Diptera. Moreover, there was no significant difference in the level of specialization between the two groups in the pollen-transport networks, though the Syrphidae had significantly greater visitation evenness. Flower visitation data from 33 farms showed that non-syrphid Diptera made up the majority of the flower-visiting Diptera in the agricultural studies (on average 82% abundance and 73% species richness), and we estimate that non-syrphid Diptera carry 84% of total pollen carried by farmland Diptera. As important pollinators, such as bees, have suffered serious declines, it would be prudent to improve our understanding of the role of non-syrphid Diptera as pollinators.

Show MeSH
Related in: MedlinePlus