Date of this Version
Presented at 2011 Bird Strike North America Conference, September 12-15, 2011, Niagara Falls, Ontario, Canada.
Bird numbers over a 12 month period were reduced by an average of 87% in large scale demonstration sowings that compare AVANEX™ tall fescue with existing airport vegetation at three New Zealand airports: Christchurch, Hamilton and Auckland.
Scientific data from trials comparing AVANEX™ tall fescue and perennial ryegrass with unselected wild-type fungal endophytes in the same cultivars show a significant reduction of 69% for above ground insects and 88% for below ground insects, over three seasons.
The advantages of fungal endophyte-enhanced grasses for bird management at airports have been discussed now for some years. The concept of a grass harbouring fewer insects that also induces avoidance behaviour by birds grazing the forage due to a unique fungal endophyte is now being exploited as an effective enhancement to wild-life management.
We first introduced the concept at this conference in Minneapolis 1999. As a consequence some airports have used unselected wild-type endophytes in tall fescue cultivars but the results have been unspectacular with sometimes poor plant survival levels (10-70%) and no convincing bird data. This paper explains some of the reasons why airport managers that use off-the-shelf unselected wild-type endophyte-infected grasses may become disillusioned by its impact on bird numbers.
The use of these grasses at airports is dependant solely on the production of good seed that contains the appropriate selected endophyte with a high level of viability. Obtaining such seed lines is not easily achieved and is the result of a new science that has had considerable research over the last 25 years in New Zealand and the USA. Knowledge of how to maintain endophyte viability in all phases: seed production, harvesting, drying, storage and distribution in the wholesale/retail chain, are now understood.
Grass renewal is a long term strategy of controlling wild-life at airports that must be based on reducing the attractiveness of the area so there are fewer bird visitations. Airport managers need to be sure their choice of grass/endophyte has had the appropriate research undertaken to provide data to give them confidence of a reliable proven product. The AVANEX™ product, a novel endophyte-infected grass that deters birds, has been tested and shown to be reliable. It is now available through PGG Wrightson Seeds.
The knowledge required to improve plant germplasm through selection in plant breeding has been well developed and exploited by man to improve the efficiency of food production. What is less well known is the selection of endophytes from wildtypes to improve the expression of alkaloids to deter insects and reduce bird grazing, and to inoculate these endophytes into plant genetic material for a specific purpose. The development of AVANEX™ is the result of over 12 years of selecting and testing prototypes of grass-endophytes to produce a unique product for airports in temperate areas. Pennell & Rolston (2010) describe the process of the development and selection of this material. A continental-type turf tall fescue grass cultivar “Jackal” was identified as ideal for airports, having tough wearing characteristics for wheel braking and able to withstand low fertility, drought-prone and compacted soils once established. A selected fungal endophyte (Neotyphodium coenophialum) called AR601 was inoculated into 60 seedlings of Jackal. These plants were then further selected for high levels of alkaloid expression (lolines as an insect deterrent and ergovaline as a bird deterrent) with 20 plants selected for further multiplication. The resulting grass-endophyte combination was named AVANEX™. Once sufficient seed was available plants were tested on an active airfield for endophyte plant density, alkaloid expression and insect presence compared with a cultivar infected with an unselected wild-type endophyte (Table 1). A similar programme was completed for a continental perennial ryegrass cultivar ‘Colosseum’ which is now also marketed under the AVANEX™ brand. It has been developed for wild-life management at parks, reserves and recreational areas.