Regulators are acutely aware of the need for meaningful risk assessments to support
decisions on the safety of GM crops to non-target invertebrates in determining their
suitability for field release. We describe a process for developing appropriate, testable
risk hypotheses for invertebrates in agroecosystems that might be exposed to plants
developed by GM and future novel technologies. An existing model (PRONTI) generates a
ranked list of invertebrate species for biosafety testing by accessing a database of
biological, ecological and food web information about species which occur in cropping
environments and their potential interactions with a particular stressor (Eco
Invertebase). Our objective in this contribution is to explore and further utilise these
resources to assist in the process of problem formulation by identifying potentially
significant effects of the stressor on the invertebrate community and the ecosystem
services they provide. We propose that for high ranking species, a conceptual food web
using information in Eco Invertebase is constructed, and using an accepted regulatory risk
analysis framework, the likelihood of risk, and magnitude of impact for each link in the
food web is evaluated. Using as filters only those risks evaluated as likely to extremely
likely, and the magnitude of an effect being considered as moderate to massive, the most
significant potential effects can be identified. A stepwise approach is suggested to
develop a sequence of appropriate tests. The GM ryegrass plant used as the “stressor” in
this study has been modified to increase triacylglyceride levels in foliage by 100% to
increase the metabolisable energy content of forage for grazing animals. The high-ranking
“test” species chosen to illustrate the concept are New Zealand native species
Wiseana cervinata (Walker) (Lepidoptera: Hepialidae),
Persectania aversa (Walker) (Lepidoptera: Noctuidae), and the
self-introduced grey field slug, Deroceras reticulatum (Müller).