Invasive predators affect community-wide pollinator visitation
Data files
Sep 08, 2021 version files 41.16 KB
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Ants.csv
8.81 KB
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Pollinators.csv
8.75 KB
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Rodents.csv
18.33 KB
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Wasps.csv
5.26 KB
Abstract
Disruption of plant-pollinator interactions by invasive predators is poorly understood but may pose a critical threat for native ecosystems. In a multi-year field experiment in Hawaiʻi, we suppressed abundances of globally invasive predators and then observed insect visitation to flowers of six native plant species. Three plant species are federally endangered (Haplostachys haplostachya, Silene lanceolata, Tetramolopium arenarium) and three are common throughout their range (Bidens menziesii, Dubautia linearis, Sida fallax). Insect visitors were primarily generalist pollinators, including taxa that occur worldwide such as solitary bees (e.g., Lasioglossum impavidum), social bees (e.g., Apis mellifera), and syrphid flies (e.g., Allograpta exotica). We found that suppressing invasive rats (Rattus rattus), mice (Mus musculus), ants (Linepithema humile, Tapinoma melanocephalum), and yellowjacket wasps (Vespula pensylvanica) had positive effects on pollinator visitation to plants in 16 of 19 significant predator-pollinator-plant interactions. We found only positive effects of suppressing rats and ants, and both positive and negative effects of suppressing mice and yellowjacket wasps, on frequency of interactions between pollinators and plants. Model results predicted that predator eradication could increase frequency of insect visitation to flowering species, in some cases by >90%. Previous results from the system showed that these flowering species produced significantly more seed when flowers were allowed to outcross than when flowers were bagged to exclude pollinators, indicating limited autogamy. Our findings highlight the potential benefits of suppression or eradication of invasive rodents, ants, and yellowjackets in order to reverse pollination disruption, particularly in locations with high numbers of at-risk plant species or already imperiled pollinator populations.
Ants.csv: A two-column dataset that specifies the number of ants at each monitoring station (column one) used for statistical analysis, in each plot and block of the experiment, during each half-year time period, with the accompanying treatment code (1-60; column 2). The treatment code is unique for each block/plot/half year combination. (See "Treatment Codes for Ant and Yellowjacket data" below.) Ants were monitored at all plots and blocks within the experiment.
Rodents.csv: An 8-column dataset that specifies the plot (column 1), block (column 2), half-year period (column 3), date of monitoring (column 4), monitoring station number (column 5), rat presence (column 6), mouse presence (column 7), and treatment code (column 8). Plot codes are as follows: ALL = Combined treatment plot, C = Untreated plot, R = Rodent treatment plot. Treatment codes for rodents do not match those for ants and yellowjackets, and are treated differently in the statistical code. Rodents were monitored at only Combined, Untreated, and Rodent treatment plots, across all blocks, during the experiment.
Wasps.csv: A two-column dataset that specifies the number of yellowjackets at each monitoring station (column one) used for statistical analysis, in each plot and block of the experiment, during each half-year time period, with the accompanying treatment code (1-60; column 2). The treatment code is unique for each block/plot/half year combination. (See "Treatment Codes for Ant and Yellowjacket data" below.) Yellowjackets were monitored at all plots and blocks within the experiment.
Pollinators.csv: A nine-column dataset the specifies the number of pollinator individuals within each pollinator group (columns 4-9) observed for each plant species (specified in column 2), accompanied by the number of observation trials (column 3), and the treatment code for the plot/block/half-year combination (column 1). Treatment codes match those for ant and yellowjacket data. (See "Treatment Codes for Ant and Yellowjacket data" below.) Plant species are as follows: BID = Bidens menziesii, DUB = Dubautia linearis, HAP = Haplostachys haplostachya, SID = Sida fallax, SIL = Silene lanceolata, TET = Tetramolopium arenarium. Pollinator groups are as follows: APIMEL = Apis mellifera, LEPIDOPTERA = moths and butterflies of multiple species, NONSDIPTERAN = Non-syrphid flies of multiple species, NONVWASP = Non-Vespula wasps of multiple species, SOLBEE = Solitary bees of multiple species, SYRPHID = Syrphid flies of multiple species. The number of Trials equates to the number of times within a plot/block/half-year period that pollinator observations were performed on the specified plant species. "NA" in the "Trials" and all pollinator group columns indicates that no pollinator observations were performed on that plant species in that plot/block/half-year period. "0" in the pollinator group columns indicates that although pollinator observations were performed on the specified plants species in that plot/block/half-year period, no individuals of that pollinator group were observed.
Treatment Codes for Ant and Yellowjacket data:
1 = Block 1, Ant treatment Plot, 1st Half Year Period
2 = Block 1, Ant treatment Plot, 2nd Half Year Period
3 = Block 1, Ant treatment Plot, 3rd Half Year Period
4 = Block 2, Ant treatment Plot, 1st Half Year Period
5 = Block 2, Ant treatment Plot, 2nd Half Year Period
6 = Block 2, Ant treatment Plot, 3rd Half Year Period
7 = Block 3, Ant treatment Plot, 1st Half Year Period
8 = Block 3, Ant treatment Plot, 2nd Half Year Period
9 = Block 3, Ant treatment Plot, 3rd Half Year Period
10 = Block 4, Ant treatment Plot, 1st Half Year Period
11 = Block 4, Ant treatment Plot, 2nd Half Year Period
12 = Block 4, Ant treatment Plot, 3rd Half Year Period
13 = Block 1, Combined treatment Plot, 1st Half Year Period
14 = Block 1, Combined treatment Plot, 2nd Half Year Period
15 = Block 1, Combined treatment Plot, 3rd Half Year Period
16 = Block 2, Combined treatment Plot, 1st Half Year Period
17 = Block 2, Combined treatment Plot, 2nd Half Year Period
18 = Block 2, Combined treatment Plot, 3rd Half Year Period
19 = Block 3, Combined treatment Plot, 1st Half Year Period
20 = Block 3, Combined treatment Plot, 2nd Half Year Period
21 = Block 3, Combined treatment Plot, 3rd Half Year Period
22 = Block 4, Combined treatment Plot, 1st Half Year Period
23 = Block 4, Combined treatment Plot, 2nd Half Year Period
24 = Block 4, Combined treatment Plot, 3rd Half Year Period
25 = Block 1, Untreated Plot, 1st Half Year Period
26 = Block 1, Untreated Plot, 2nd Half Year Period
27 = Block 1, Untreated Plot, 3rd Half Year Period
28 = Block 2, Untreated Plot, 1st Half Year Period
29 = Block 2, Untreated Plot, 2nd Half Year Period
30 = Block 2, Untreated Plot, 3rd Half Year Period
31 = Block 3, Untreated Plot, 1st Half Year Period
32 = Block 3, Untreated Plot, 2nd Half Year Period
33 = Block 3, Untreated Plot, 3rd Half Year Period
34 = Block 4, Untreated Plot, 1st Half Year Period
35 = Block 4, Untreated Plot, 2nd Half Year Period
36 = Block 4, Untreated Plot, 3rd Half Year Period
37 = Block 1, Rodent treatment Plot, 1st Half Year Period
38 = Block 1, Rodent treatment Plot, 2nd Half Year Period
39 = Block 1, Rodent treatment Plot, 3rd Half Year Period
40 = Block 2, Rodent treatment Plot, 1st Half Year Period
41 = Block 2, Rodent treatment Plot, 2nd Half Year Period
42 = Block 2, Rodent treatment Plot, 3rd Half Year Period
43 = Block 3, Rodent treatment Plot, 1st Half Year Period
44 = Block 3, Rodent treatment Plot, 2nd Half Year Period
45 = Block 3, Rodent treatment Plot, 3rd Half Year Period
46 = Block 4, Rodent treatment Plot, 1st Half Year Period
47 = Block 4, Rodent treatment Plot, 2nd Half Year Period
48 = Block 4, Rodent treatment Plot, 3rd Half Year Period
49 = Block 1, Yellowjacket treatment Plot, 1st Half Year Period
50 = Block 1, Yellowjacket treatment Plot, 2nd Half Year Period
51 = Block 1, Yellowjacket treatment Plot, 3rd Half Year Period
52 = Block 2, Yellowjacket treatment Plot, 1st Half Year Period
53 = Block 2, Yellowjacket treatment Plot, 2nd Half Year Period
54 = Block 2, Yellowjacket treatment Plot, 3rd Half Year Period
55 = Block 3, Yellowjacket treatment Plot, 1st Half Year Period
56 = Block 3, Yellowjacket treatment Plot, 2nd Half Year Period
57 = Block 3, Yellowjacket treatment Plot, 3rd Half Year Period
58 = Block 4, Yellowjacket treatment Plot, 1st Half Year Period
59 = Block 4, Yellowjacket treatment Plot, 2nd Half Year Period
60 = Block 4, Yellowjacket treatment Plot, 3rd Half Year Period