Eastern Pine and Meadow Vole Symposia

Registration List

Wed, 18 Jun 2008 07:22:35 PDT

Highlights of the Seventh Eastern Pine and Meadow Vole Symposium

Ross E. Byers — Wed, 18 Jun 2008 07:12:33 PDT

The Seventh Eastern Pine and Meadow Vole Symposium was held at the Cliffside Inn, Box 786, Harpers Ferry, West Virginia, March 3-4, 1983 for the purpose of assessing the current status of research, extension, and industry programs relating to vole damage to fruit trees. The meeting was held to provide a problem solving atmosphere in which growers, governmental agencies such as EPA, USDA, USDI, the chemical industry, and university personnel could observe the current thrusts of research and extension programs and their impact on future control strategies.

Registration List

Wed, 18 Jun 2008 07:03:44 PDT

Highlights of the Third Eastern Pine and Meadow Vole Symposium

Ross E. Byers — Wed, 18 Jun 2008 07:03:40 PDT

The Third Eastern Pine and Meadow Vole Symposium was held in New Paltz, New York, February 14-15, 1979 to further create an awareness of the fruit growers' serious tree girdling problem. The meeting served to focus attention on a diversity of information on animal biology, control strategies and information dispensing mechanisms. Research funding sources, chemical and cultural control methods, clearance of new materials, and governmental involvement in pine vole problems were discussed.

Behavioral Responses of Pine Vole Young and Adults to Olfactory Cues

Lynette A. Geyer — Wed, 18 Jun 2008 06:48:24 PDT

Ultrasonic vocalization rates of young pine voles are highest when pups begin to move into and out of nests and exhibit olfactory directed movement. As olfactory preferences become established and movement is coordinated, a decline in vocalization appears in pine vole. In the presence of home shavings young pine voles emit high rates of vocalization, while rat pups emit calls at a low rate. This contrast may relate to the intensive attachment of young pine voles to the mother in early life. In preliminary studies of adults, priming either the male or female with the odor of a prospective social partner reduces subsequent aggression. While long-term olfactory exposure can familiarize a vole with an unknown conspecific and reduce conflict, a brief unfamiliar olfactory stimulus to a male can disrupt subsequent interactions of a familiar pair.

The Endrin RPAR

Lawrence S. Ebner — Tue, 17 Jun 2008 10:00:39 PDT

In July, 1976 the U.S. Environmental Protection Agency issued a "Notice of Rebuttable Presumption Against Registration and Continued Registration of Pesticide Products Containing Endrin" (41 Fed. Reg. 31,316). The purpose of this Notice was to initiate an "RPAR" review to determine whether continued usage of endrin, including the use of endrin for vole control, poses a "substantial question of safety" necessitating cancellation proceedings under Section 6(b) of the Federal Insecticide, Fungicide and Rodenticide Act ("FIFRA").

Pine Vole Control Surveying

Fred M. Strawson — Tue, 17 Jun 2008 09:48:07 PDT

I don't have an orchard of my own, but as a field representative for FMC Corp. Direct Sales Group, I have the responsibility to check for mice in many orchards and a chance to form an opinion as to what methods are working in our area and how a field representative can be of the most value.

Registration List

Tue, 17 Jun 2008 06:58:17 PDT

Registration List

"Mouse-Ateria" - A Bait Station for Rodents

Bruce Porterfield et al. — Tue, 17 Jun 2008 06:43:36 PDT

In 1918 the first device of this kind was designed near Winchester, Virginia. In 1973 we introduced a high strength Styrene plastic version of it, copied from the hand-blown glass model.

Control of Microtus in Two Damage Situations

Andrew Radvanyi — Tue, 17 Jun 2008 06:22:16 PDT

In Canada the potential exists of over a million dollars girdling damage loss per year caused by small mammals to fruit trees in each of the four major orchard areas of British Columbia, Ontario, Quebec and Nova Scotia. Such annual losses continue to occur despite the existence of methods developed which could largely eliminate a large percentage of such losses at a fraction of the costs currently being spent on attempts to control small mammal populations (primarily meadow voles (Microtus pennsylvanicus) in orchard situations. In this paper I propose to outline briefly the developmental studies conducted by the Canadian Wildlife Service in research involving harmful small mammal populations on a hardwood plantation in southern Ontario and on a similar reclamation and afforestation program being conducted in the tar sands area of northeastern Alberta. I propose that the techniques developed in these studies hold considerable potential should they be applied to orchard damage situations such as those with which this symposium is concerned.

VELSICOL MARKETS MORE THAN A RODENTICIDE

Velsicol Chemical Corporation — Fri, 30 May 2008 14:00:00 PDT

Manufacturer's responsibility does not end with production of a high quality bait. There are several excellent rodenticides on the market today, but their effectiveness depends on the applicators understanding of what he is doing and why he is doing it. That's why Velsicol has shifted so much of its emphasis to studying rodent behavior and rodenticide application technology. To provide orchardists with an understanding of the dynamics of orchard vole control, Velsicol developed an educational program based on integration of good management practices with chemical and non-chemical methods of control. The program covers orchard cultural practices, identification of voles, vole ecology, and, mechanical and chemical methods of control. It emphasizes that chemicals much be used in conjunction with good cultural practices to optimize production and protect the growers investment.

1982-83 TOXICANT VOLE CONTROL

Roger S. Young — Fri, 30 May 2008 13:59:56 PDT

EFFICACY OF SPRING BROADCAST RODENTICIDES IN THE HUDSON VALLEY, NEW YORK

Paul F. Steblein et al. — Fri, 30 May 2008 13:40:19 PDT

Subsequent to the prohibition of endrin use in New York State, a variety of alternate rodenticides and methods of rodenticide application have been examined in an effort to develop effective control measures for the pine vole, Pitymys pinetorum. These studies indicate that the manner in which the rodenticides are applied substantially influences their effectiveness in controlling pine voles. Specifically, in our experience placing poisoned bait directly in the animal’s subsurface tunnel systems has proved to be the most effective means of vole control. However, this method of bait placement is both time consuming and expensive. An alternate more cost-effective method of applying rodenticides is that of broadcast application. However, broadcast applications of rodenticides have been inconsistent in their effects in controlling pine voles (Richmond et al. 1978). The equivocal results produced by this method may be related to the timing of its use on a seasonal basis. Traditionally, orchards have been treated in the fall after apple harvest, but prior to vegetation dieback when abundant food resources may influence bait acceptability (Steblein and Richmond 1982). Indeed, McAninch (1981) found that broadcast treatments were most effective in reducing vole population size when treatments were carried out after the senescence of ground vegetation in the fall. The influence of a spring broadcast prior to grass greenup on vole populations remains unexplored. Thus, in this study we examine the efficacy of two anticoagulants, Bromodiorone (Maki, Chemparl and Brodificoum (Volid, ICI Americas, Inc.), and a toxicant, zinc phosphide (ZP Rodent Bait, Bell Laboratories) when applied using broadcast techniques in early spring.

LONG TERM VOLE CONTROL IN ONTARIO APPLE ORCHARDS

Zia Siddiqi et al. — Fri, 30 May 2008 13:13:25 PDT

The results obtained so far in this 3 year study have shown that the plots with poisoned bait feeder stations suffered significantly less tree girdling than the plots treated with the fall broadcast application of 2% zinc phosphide. Similar timings were also observed in number of voles per plot, however, the vole population was much lower than the previous year. Considerable interest has been shown by apple growers in adopting this method of vole control at a commercial level.

SOCIAL INFLUENCES ON REPRODUCTION IN PINE VOLES

Margaret H. Schadler — Fri, 30 May 2008 12:35:04 PDT

The presence of large populations of pine voles in apple orchards suggests that in the field reproduction of these pests has few constraints. Yet, evidence collected from our colony at Union College indicates that in the laboratory reproduction is not at random but instead is socially restrained and predictable. Unless these findings are artifacts of laboratory life, they may help explain some of the data collected in the field. Horsfall (1963) trapped voles every month of the year from an orchard near Cloverdale, VA. Since he found pregnant females in all collections, he concluded that reproduction occurred throughout the year with a peak in the summer months. On the other hand, Valentine and Kirkpatrick(1970) found pregnant females in only seven months of the year in orchards near Danville, VA. The conflict in data has not been resolved and may be a result of social factors that could not be determined in the field. In the laboratory, we found that reproduction in pine voles is influenced by a variety of social conditions.

EFFECTS OF THREE PINE VOLE POPULATIONS ON APPLE TREE GROWTH AND PRODUCTIVITY

Milo Richmond et al. — Fri, 30 May 2008 09:25:34 PDT

Few attempts have been made to quantify the damage to agricultural crops resulting from known densities of a particular pest. Availability of such information, even in its most basic form, is essential to making cost-effective management decisions. The question seems straightforward and simple; however, it is neither. For example, the damage caused by rodents in an apple orchard is not easily observed or measured. Moreover, the ultimate economic effects are dependant to s.ome degree upon tree age, variety and replacement cost; weather, productivity market prices, and a host of other manageable and unmanageable factors facing the grower. In addition to these variables we must admit to not knowing exactly how the degree of girdling damage relates to health and vigor of the tree nor do we understand cumulative or recuperative factors which likely affect a perennial species. We do have evidence that compensatory growth can occur in certain damage situations (see for example Dyer 1973, 1975, 1976; Harris 1974; Hutchinson 1971; Pearson 1965; Vickery 1972; Westlake 1963 and Woronecki et al. 1976). So, while the problem appears clear the answer can be obfuscated by a host of variables many of which can change in a single season.

THE INFLUENCE OF SOIL MOISTURE, TEXTURE, AND TEMPERATURE ON NEST-SITE SELECTION AND BURROWING ACTIVITY BY THE PINE VOLE, MICROTUS PlNETORUM

Donald H. Rhodes et al. — Fri, 30 May 2008 09:25:29 PDT

Pine voles (Microtus pinetorum) have long been recognized as a pest species in fruit orchards of the eastern United States (Hamilton 1935). These semifossorial rodents construct tunnel systems beneath apple trees where they eat entire roots or strip roots of bark and cambium. Hamilton (1938) reported numbers of pine voles within apple orchards as high as 200-300 voles per acre which is in sharp contrast to the relative scarcity of pine voles outside orchard situations (Crain and Packard 1966; Goertz 1971), These findings suggest that orchard habitat provides excellent conditions for pine vole growth and reproduction, although the specific components which are attractive to pine voles and facilitate their proliferation remain poorly understood. Prior studies have suggested that pine vole habitat selection is based on preference for a complex of habitat components including cover density (Benton 1955; Paul 1970; Goertz 1971), food resources (Noffsinger 1976), soil texture (Fisher and Anthony 1980), and soil moisture (Haines and Gier 1951; Miller 1964). With regard to the latter two variables, Miller (1964) and Best (1973) have presented evidence indicating that soil texture is a primary factor limiting the distribution of some fossorial mammals but soil moisture content may also be of importance (Miller 1948). The extent to which these soil properties influence the distribution and abundance of pine voles is presently unclear. Similarly, pine vole response to soil temperature remains unexplored. Thus, in this study we examine the influence of soil texture, moisture, and temperature on nest site selection and burrowing activity of the pine vole, Microtus pinetorum.

The Efficacy of Several Broadcast Rodenticides in the Mid-Hudson Valley, New York

Ralph Pagano et al. — Fri, 30 May 2008 08:44:19 PDT

As summarized by LaVoie and Tietjen (1978), many aspects of vole control using rodenticides including the costs/benefits of rodenticide use, applicator limitations in commercial orchards, and vole biology have not received proper attention. Data relating vole population levels to damage severity have not been generated and thus the exact benefits of control measures are difficult to analyze. Several aspects of vole biology have only recently been considered in rodenticide application procedures. Problems such as bait acceptance and percentage population control have created disparity in several rodenticide experiments (Richmond et al., 1978). A knowledge of vole use of vegetative cover and food habits is critical to the timing and effectiveness of population control via rodenticide. Several of these points were developed into the objectives for the projects completed in the Fall 1981 and 1982.

Movements and Habitat Use by Pine and Meadow Voles in an Orchard

Ralph E. Pagano — Fri, 30 May 2008 08:13:41 PDT

Several radiotelemetry studies have now been completed in the orchards of the mid-Hudson Valley, New York. The results of one of these projects, a l2-month study of the movements and habitat use of pine and meadow voles, will be reported on here. The success of an integrated vole management program using cultural practices and rodenticides depends a great deal on knowing the movements and habitat use of the two orchard vole species. Species interactions that could lead to differential use of the orchard habitat are another important element in a vole management program. This study focused on three major objectives: 1. To determine if differences in habitat use and movements existed between pine and meadow voles. 2. To determine if the habitat use and movement patterns of each species changed seasonally. 3. To integrate this information into a vole management program.

RESULTS OF 1982 RODENTICIDE FIELD TESTS

M. H. Merson et al. — Fri, 30 May 2008 07:38:42 PDT

A 2.0% zinc phosphide pellet and a 0.001% brodifacoum bait gave the lowest percentage post-treatment activity in a field test in which broadcast applications were followed shortly by rain. There was not a clear difference in performance between the single-feeding toxicants and the multiple-feeding anticoagulants in this experiment. A 0.075% cholecalciferol bait gave control comparable to some registered materials and shows promise for future development. A bait containing 0.0216% diphacinone gave significantly better control than one containing 0.005% diphacinone.