Introduction
What hypothesis were the authors testing?
They tested the hypothesis that major groups of pollinating insects differ in their responses to urbanization as a result of taxon-specific habitat requirements.
In Leicester, what was the abundance of hoverflies?
1524
How many species of insects did the authors end up collecting?
302 species.
For every 10% increase in impervious surfaces, what was the effect on pollinating insects?
A reduction of up to 7.5% species richness.
This study took place in the UK. What species of hoverfly found in the UK would probably be Paddington Bear's favourite?
The Marmalade Hoverfly
Numerous studies have documented the effects of urbanization on individual pollinator taxa. What knowledge gap did the authors identify with these studies?
There aren't (or weren't when the paper came out) very many comparative studies looking at different taxa's relative risks.
What specific type of explanatory variable were the cities?
A three‑level factorial variable.
Why did the authors argue that conserving pollinator biodiversity was important?
Pollinator biodiversity increases functional redundancy and buffers pollination against species loss, partially since taxa differ in plant visitation, especially between diurnal and nocturnal pollinators.
What's Erika's favourite moth?
The Luna Moth (which is not found in the UK).
What two groups do the authors categorize their insects as?
Diurnal and nocturnal pollinating insects.
Why were multiple methods of sampling insects used?
Each sampling method had strengths and biases, so by using multiple techniques, the authors helped compensate for each method's biases.
Which city showed the greatest consistency of pollinator responses to increasing urbanization at all scales?
Leicester.
Private gardens comprised around 23.3% of the greenspace in the three cities, but didn't have any significant effect on pollinator abundance or species richness at any scale. Why do the authors think this is the case?
In the paper, ArcGIS was used to quantify landscape variables at three spatial scales. Which of your presenters has the most experience using ArcGIS?
Ailsa
What suggested that flies and moths might be affected more by urbanization compared to bees?
Variation in niche breadth.
The dispersal abilities of some of the taxa looked at exceeded the distance between sites within some of the cities. Why did the authors of the paper not consider this is be consequential?
Habitat fragmentation, topographic barriers, and other features of urban environments would prevent most insects from moving in between sites.
The authors wanted to reduce sampling bias by using multiple sampling methods. Did this generally succeed?
Yes, while Malaise traps and sweep nets caught different numbers of individuals and each Malaise traps caught most of the hoverflies whereas sweep nets caught most of the bees, the pollinator groups had similar sampling coverage overall.
How much bee abundance was made up by social bees?
88% of bee abundance.
The authors of this paper did their analyses in R v. 4.12. What's the code name for this version of R?
Why wouldn't you expect moths to benefit very much from flower beds within urban environments?
Moths need sheltered habitat like shrubs and trees.
Apart from having different levels of urbanization, there was another difference between the cities in the study. What was that difference and why does it matter?
The cities also differed in size, which was important because unlike the other two cities, Leicester was too small to have its sites placed two or more kilometers apart. Instead, the authors had to place the sites a minimum of one kilometer apart.
What species of insect had the most specimens collected across all the cities?
Sphaerophoria scripta (1014).
What are some limitations of bee pollination that are made up for by the other taxa?
Bees cannot transfer pollen as great distances as hoverflies can and they cannot pollinate plants that only produce nectar at night like moths can.
How far from Leeds is Sheffield in inches?
1,850,388 inches