| Title |
Invasive rats alter woody seedling composition on seabird-dominated islands in New Zealand
|
|---|---|
| Published in |
Oecologia, December 2009
|
| DOI | 10.1007/s00442-009-1523-6 |
| Pubmed ID | |
| Authors |
Madeline N. Grant-Hoffman, Christa P. Mulder, Peter J. Bellingham |
| Abstract |
Invasive rats (Rattus rattus, R. norvegicus, R. exulans) have large impacts on island habitats through both direct and indirect effects on plants. Rats affect vegetation by extirpating burrowing seabirds through consumption of eggs, chicks, and adults. These seabirds serve as ecosystem engineers, affecting plant communities by burying and trampling seeds and seedlings, and by altering microclimate. Rats also directly affect plant communities by consuming seeds and seedlings. We studied the direct and indirect impacts of rats on the seedlings of woody plants on 21 islands in northern New Zealand. We compared seedling densities and richness on islands which differed in status with respect to rats: nine islands where rats never invaded, seven islands where rats were present at the time of our study, and five islands where rats were either eradicated or where populations were likely to be small as a result of repeated eradications and re-invasions. In addition, we compared plots from a subset of the 21 islands with different burrow densities to examine the effects of burrowing seabirds on plants while controlling for other factors that differ between islands. We categorized plant communities by species composition and seedling density in a cluster analysis. We found that burrow densities explained more variation in seedling communities than rat status. In areas with high seabird burrow density seedling densities were low, especially for the smallest seedlings. Species richness and diversity of seedlings, but not seedling density, were most influenced by changes in microclimate induced by seabirds. Islands where rats had been eradicated or that had low rat populations had the lowest diversity and richness of seedlings (and adults), but the highest seedling density. Seedling communities on these islands were dominated by Pseudopanax lessonii and Coprosma macrocarpa. This indicates lasting effects of rats that may prevent islands from returning to pre-invasion states. |
Mendeley readers
The data shown below were compiled from readership statistics for 57 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 2 | 4% |
| United Kingdom | 2 | 4% |
| Portugal | 1 | 2% |
| Australia | 1 | 2% |
| Spain | 1 | 2% |
| New Zealand | 1 | 2% |
| Unknown | 49 | 86% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Ph. D. Student | 20 | 35% |
| Researcher | 10 | 18% |
| Student > Bachelor | 6 | 11% |
| Student > Master | 5 | 9% |
| Student > Postgraduate | 4 | 7% |
| Other | 9 | 16% |
| Unknown | 3 | 5% |
| Readers by discipline | Count | As % |
|---|---|---|
| Agricultural and Biological Sciences | 33 | 58% |
| Environmental Science | 9 | 16% |
| Biochemistry, Genetics and Molecular Biology | 2 | 4% |
| Earth and Planetary Sciences | 2 | 4% |
| Arts and Humanities | 1 | 2% |
| Other | 5 | 9% |
| Unknown | 5 | 9% |
Attention Score in Context
This research output has an Altmetric Attention Score of 3. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 02 December 2016.
All research outputs
#7,451,584
of 22,780,967 outputs
Outputs from Oecologia
#1,672
of 4,210 outputs
Outputs of similar age
#48,417
of 164,176 outputs
Outputs of similar age from Oecologia
#9
of 21 outputs
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