Beetle Monitoring

2007-2009 Critical Monitoring of Tamarisk
Biological Control Activities in Eastern Utah & Western Colorado

NEW- 2010 Public Presentations

In January, the Tamarisk Coalition will present the results of their third year of monitoring the distribution of the tamarisk leaf beetle, Diorhabda spp. in the Colorado River Watershed in Page, AZ on January 19th. Please see the beetle presentation schedule for further details. If you are unable to attend a public presentation, you may view slides from the talk in a pdf format here. A comprehensive map displaying the results of this year's monitoring is now available.

Background

Biological control, or bio-control, uses specific organisms to control an undesirable organism, in this case tamarisk. The tamarisk biological control agent, Diorhabda spp., is providing an active 2,000 mile experiment throughout the upper Colorado Plateau. Diorhabda spp., or the tamarisk leaf beetle, works to control tamarisk by repeatedly defoliating the plant over several years. Preliminary evidence of effectiveness shows great potential. If effective, biocontrol offers some significant advantages over other tamarisk control approaches; i.e., limited use of herbicides and a cost-effectiveness. 

Monitoring these beetle populations is critical to provide insight and data on their direct and indirect impacts on the riparian ecosystem. In 2007, the Tamarisk Coalition, in partnership with the Palisade Insectary, identified the need for this immensely important activity and made the decision to initiate beetle monitoring efforts on the Colorado and Green Rivers.

• NEW- 2009 Diorhabda spp. Distribution Map
• 2008 Diorhabda spp. Distribution Map
• 2007 Colorado River Beetle Distribution Chart
• 2008 Dolores River Beetle Distribution Chart
• National Park Service Investigator's Annual Report (IAR)-2007 Monitoring

The Coalition’s 2009 monitoring program is part of a multi-year effort to support a body of knowledge that will determine the distribution of the beetle, Diorhabda spp., as well as vegetative response, on these three river systems. The goals of this monitoring program are -

1. To obtain data concerning the dispersal and establishment of Diorhabda spp.;
2. To monitor tamarisk defoliation;
3. To identify the response of native vegetation and of invasive weed species to tamarisk bio-control.

In February 2009, the Tamarisk Coalition was awarded a grant to undertake a more comprehensive monitoring effort characterizing diverse ecosystem changes that may accompany the Diorhabda beetles. Tamarisk Coalition field crews will spend late May to early September systematically measuring beetle activity and vegetative responses in the designated survey area. Additionally, biologists from the Rocky Mountain Bird Observatory will perform bird population surveys in order to monitor potential impacts to bird populations in riparian areas. At the end of the field season, the data collected will be disseminated to researchers, resource managers, and the general public. The project goal is to paint a clear picture of a changing ecosystem and to facilitate efficient management of the affected riparian areas.

Monitoring Protocols

In general the goal of the biocontrol monitoring protocol is to define when, where, and how many Diorhabda spp. are in existence across the region. Within that we then want to have a good idea of where defoliating sized populations exist, where newly aggregated populations are rising, and where beetles have yet to spread to. This protocol is designed to be fast and efficient and answer only basic questions about Diorhabda spp.distribution and abundance. It can be utilized on and off the river and should be a basic protocol for establishing the degree of beetle presence in an area.

Safety

Established safety protocols are followed for both river and camping safety. Two-person field crews have at least one technician certified in Wilderness First Responder on all trips. Appropriate river use and research permits have been acquired from both the BLM and National Park Service (BLM permit # J-381, NPS permit # 51838). Additionally, all field crews follow Leave No Trace practices to minimize their impact on the riparian corridor.