Being Bugged By Biocontrol

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BY SYDNEY ROSS SINGER – The bugging of Hawaii’s strawberry guava is back on the table with the recently proposed environmental assessment for the introduction of a scale insect from Brazil, Tectococcus ovatus, to infest these trees statewide.

The insect will cause disfiguring and disabling galls on the leaves of the trees, with the hope that this will reduce fruit production and slow the spread of this species.


As the government considers this proposal during the 30-day comment period, which ends July 23, 2010, you should be aware of some of the problems with biocontrol that the scientists invested in this method are not telling you.

Biocontrol “agents” include insects, fungi, and other biological agents to infest, disease, predate, eat, or in some other way weaken species which are labeled as “invasive.”

Conflicts over the use of biocontrol are global, not just here in Hawaii. Interestingly, however, more biocontrol research is done in Hawaii than anywhere else in the world, since our isolation makes us a safe test site for the rest of the planet. Of course, that is not comforting to those of us who live here.

Here are a few of the problems with biocontrol.

  • Biocontrol insects and fungi are introduced without any of their predators. This means they can grow out of control, just like the species they are supposed to be controlling. What will control them?
    Realize that newly introduced insects can spread like a blitzkrieg. The wiliwili wasp destroyed trees statewide within a few years, surprising local biologists at its speed of spread. The o’hia rust (Puccinia) spread like wildfire to destroy rose apples and infest guava, strawberry guava, o’hia, eucalyptus, and more. Biocontrol insects and fungi can spread as fast.
  • All biocontrol is an experiment, and is irreversible and irrevocable. All that the scientists releasing the insects or fungi can do is monitor and observe the results of their experiment. If things go awry, the experiment cannot be stopped.
  • Scientists are lying when they say the past 30 years of biocontrol experiments have never resulted in a biocontrol agent attacking a non-target species. In 2005, it was admitted by the Hawaii Department of Agriculture that the Septoria fungus, used to attack banana poka, is also capable of attacking edible passion fruit, which was not predicted in the research prior to release.
  • Further evidence of a biocontrol agent attacking non-target species was described in an August 26, 2002 email from UH’s Forest Starr to Philip Thomas of Hawaii Ecosystems at Risk (HEAR). It states, “We were recently on the Hana Hwy. with Mach looking at the biocontrols of some of the Melastomes.
  • It appears that Clidemia beetle (Lius poseidon) has jumped to Tibouchina herbacea, and perhaps T. urvilleana. Pat Conent apparently recently documented the same thing occurring on the big island (it seems host testing before release was not done well enough to predict this.)”
  • In addition to these admissions, you should realize that less than 2% of all biocontrol releases have had any post-release monitoring to see what actually happens. This means that many non-target attacks may have happened, but unless they are accidentally discovered they will go undocumented.
  • Therefore, biocontrol proponents’ statements that these past releases over the last 30 years have not attacked non-target species is wishful thinking at best, and a lie in at least two documented cases.
  • Also realize that insect evolution and adaptation to attacking new species can occur as fast as a few years to a few decades. Fungi evolve and adapt within even less time. We may be now only starting to see the negative impacts of biocontrol experiments of the past few decades.
  • Even if a biocontrol agent does stay on target, the target may be a species that some people desire. Strawberry guava is an excellent example, and shows the problem with all “invasive species” labeling.
  • The environment consists of forests, backyards, public spaces, urban areas, and more. It is the space in which we live. A species could be a problem in one environmental context, but could be desirable in other environmental contexts.
  • Strawberry guava, for example, is a desirable ornamental fruit tree since 1825, and Hawaii officials actually promoted its use. In backyards and orchards, it is still highly appreciated by many. In that context it is desirable. However, in the forests it can grow to the detriment of less thrifty native species, making it a weed in that context.
  • The problem is that biocontrol agents do not distinguish between these contexts. If the scale insect is released to attack strawberry guava, it is expected to attack all strawberry guava trees statewide, causing property damage to desired and valued trees.
  • This creates an interesting paradox. In the context of the forests, the strawberry guava is considered the invasive and the scale insect considered beneficial. However, in the context of the orchard or backyard, strawberry guava is considered beneficial and the insect is the invasive species.
  • This is a fatal flaw of biocontrol. It is non-specific to area, and ignores property boundaries.

These are only a few of the problems with biocontrol. Others can be found at and

Clearly, biocontrol can be more of a problem than a solution, depending on what is the target species and what actually happens after the biocontrol insect, fungus or other agent is released.

It is ironic that the alleged need for biocontrol stems from the introduction of species in the past, while biocontrol simply introduces more species to attack prior introduced species, resulting in unpredictable ecosystem shifts that will likely lead to more introductions to control these biocontrol introductions.

If you don’t want these researchers to bug your plants, it is time to comment on their proposed strawberry guava infestation plan. You can read the EA here:

Only written comments will be accepted, and may be submitted to the Hawai‘i Department of Agriculture Plant Pest Control Branch at 1428 S. King St. Honolulu, HI 96814, with a copy sent to the Department of Land and Natural Resources, Division of Forestry and Wildlife, 1151 Punchbowl Street, Room 325, Honolulu, Hawaii 96813; or emailed to . Comments must be submitted by July 23.

Then consider joining a lawsuit to stop them. Contact me, SYD SINGER, at, or call 808-935-5563.