Control invasive ants on islands

Overall effectiveness category Unknown effectiveness (limited evidence)
Number of studies: 1
Share Tweet Email

View assessment score

How is the evidence assessed?

Effectiveness

10%
Certainty

15%
Harms

not assessed

Calculating overall effectiveness category

Background information and definitions

Several species of ants, including fire ants Solenopsis spp., yellow crazy ants Anoplolepis gracilipes and Argentine ants Linepithema humile have been spread over the world by human activities. Ants are key species in many ecosystems and can have enormous direct and indirect impacts on native species.

Study locations

Key messages

A replicated, randomised and controlled, before-and-after paired sites study in the USA found temporarily increased fledging success, but no decrease in injuries inflicted by Solenopsis geminata on wedge-tailed shearwaters Puffinus pacificus following ant control. However, there was no change in fledging success or injury rate on an island dominated by the big-headed ant Pheidole megacephala following its eradication, either on the experimental or control island.

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

A replicated, randomised and controlled, before-and-after paired sites study over three breeding seasons in 2002-2004 on two pairs of offshore islets (< 5 ha) in Hawaii, USA (Plentovich et al. 2009), found that wedge-tailed shearwaters Puffinus pacificus from an island previously dominated by the invasive tropical fire ant Solenopsis geminata showed temporarily increased fledging success, but no decrease in injuries inflicted by S. geminata following ant control (27-38% of chicks injured in all seasons), whilst fledging rates remained constant and injuries increased on an untreated island (8% injured in 2002, 80-100% in 2003-4). There was no change in fledging success or injury rate on an island dominated by the big-headed ant Pheidole megacephala following its eradication, either on the experimental or control island, but very few chicks were injured by ants. Severely injured chicks (20% of tissue on their feet lost) weighed significantly less than uninjured chicks and did not fledge. Between 15 and 43 chicks were monitored on each islet each year. Following a year of baseline data collection, ant populations were controlled with granular protein-based ant bait in February 2003 on one randomly selected islet of each pair.
Study and other actions tested
Referenced paper
Plentovich S., Hebshi A. & Conant S. (2009) Detrimental effects of two widespread invasive ant species on weight and survival of colonial nesting seabirds in the Hawaiian Islands. Biological Invasions, 11, 289-298.

Please cite as:

Williams, D.R., Child, M.F., Dicks, L.V., Ockendon, N., Pople, R.G., Showler, D.A., Walsh, J.C., zu Ermgassen, E.K.H.J. & Sutherland, W.J. (2020) Bird Conservation. Pages 137-281 in: W.J. Sutherland, L.V. Dicks, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2020. Open Book Publishers, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

This Action forms part of the Action Synopsis:

Bird Conservation

Related Actions

Actions	Effectiveness	Studies	Category
Control invasive ants on islands Action Link	Unknown effectiveness (limited evidence)	1	Synopsis Link
Remove or control predators to enhance bird populations and communities Action Link	Beneficial	2	Synopsis Link
Control predators not on islands for cranes Action Link	Awaiting assessment	1	Synopsis Link