Around the world in 500 years: Inter-regional spread of alien species over recent centuries
Date
2021
Journal Title
Journal ISSN
Volume Title
Publisher
John Wiley & Sons Ltd.
Abstract
Aim: The number of alien species has been increasing for centuries world-wide,
but
temporal changes in the dynamics of their inter-regional
spread remain unclear. Here,
we analyse changes in the rate and extent of inter-regional
spread of alien species
over time and how these dynamics vary among major taxonomic groups.
Location: Global.
Time period: 1500–2010.
Major taxa studied: Vascular plants, mammals, birds, fishes, arthropods and other
invertebrates.
Methods: Our analysis is based on the Alien Species First Record Database, which
comprises >60,000 entries describing the year when an alien species was first recorded
in a region (mostly countries and large islands) where it later established as
an alien species. Based on the number and distribution of first records, we calculated
metrics of spread between regions, which we termed “inter-regional
spread”, and conducted statistical analyses to assess variations over time and across taxonomic
groups.
Results: Almost all (>90%) species introduced before 1700 are found in more than
one region today. Inter-regional
spread often took centuries and is ongoing for many
species. The intensity of inter-regional
spread increased over time, with particularly
steep increases after 1800. Rates of spread peaked for plants in the late 19th century,
for birds and invertebrates in the late 20th century, and remained largely constant
for mammals and fishes. Inter-regional
spread for individual species showed hump-shaped
temporal patterns, with the highest rates of spread at intermediate alien range
sizes. Approximately 50% of widespread species showed signs of declines in spread
rates.
Main conclusions: Our results show that, although rates of spread have declined for
many widespread species, for entire taxonomic groups they have tended to increase
continuously over time. The large numbers of alien species that are currently observed
in only a single region are anticipated to be found in many other regions in the
future.
Description
CITATION: Seebens, H, Blackburn, TM, Hulme, PE, et al. Around the world in 500 years: Inter-regional spread of alien species over recent centuries. Global Ecol Biogeogr. 2021; 30: 1621– 1632. doi.10.1111/geb.13325
The original publication is available at: wiley.com
The original publication is available at: wiley.com
Keywords
Alien species -- Accumulation, Biological invasions, Alien species -- Geographical distribution, Global environmental change -- Effect of human beings on -- History, Invasion curves, Spatio-temporal data model
Citation
Seebens, H, Blackburn, TM, Hulme, PE, et al. Around the world in 500 years: Inter-regional spread of alien species over recent centuries. Global Ecol Biogeogr. 2021; 30: 1621– 1632. doi.10.1111/geb.13325