Future of Wildlife Damage Control and the Cooperative Extension Service

The driving forces which determine the role of the Cooperative Extension Service in wildlife damage control are (1) the demand for information by the public, (2) the degree of support for programs at the national level, and (3) the level of professionalism exhibited by Cooperative Extension Agents and subject matter Specialists. Analysis of several trends suggests that the Cooperative Extension Service role in Wildlife Damage Control will increase in coming years. The movement of urban people into rural settings will create greater demands for wildlife damage control information. Likewise, the expansion of wildlife population into urban and suburban environments due to creation of new habitats will generate needs for new programs in cities. The emergence of the coyote as a prominent predator on livestock in the East will result in development of new Extension education programs to help farmers deal with coyotes. Each of these increases in conflicts between people and wildlife will be met with educational programs developed and presented by the Cooperative Extension Service. However, due to the increase in social concern over the rights of animals, the quality of extension programs and recommendations will increase. The high degree of professionalism characteristic of Extension workers today will continue and even expand in the future, as better trained people join the system, more research is completed on wildlife damage control problems, and better skills are developed in developing, presenting and evaluating extension programs

STATUS AND MANAGEMENT OF VOLE DAMAGE TO HORTICULTURAL PLANTINGS IN NORTH CAROLINA

A trapping study in 1979 indicated that voles (Microtus pinetorum and M. pinetorum) were distributed widely in North Carolina. In 1991, Extension Agents with the North Carolina Cooperative Extension Service were surveyed to determine the distribution, nature and severity of vole damage to horticultural plantings, home orchards, and other plantings. Data from the statewide trapping survey and the poll of agents coincided to indicate that voles, particularly pine voles, caused damage from the mountains to the coast. Existing, legal control methods were judged grossly inadequate by agents. Pursuant to the surveys, the North Carolina Pesticide Board and the North Carolina Wildlife Resources Commission were petitioned to approve changes in the North Carolina Administrative Code to reclassify voles as pests in horticultural plantings. The rule change, published on March 3, 1993, permitted use of non-restricted rodenticides to control voles. The product recommended was Rozol Parrafinized Pellets. Extension Agents enthusiastically welcomed the change. An extension publication for home horticulturalists on controlling vole damage is in preparation

Habitat Selection of Northern Bobwhite Coveys on Two Intensive Agriculture Landscapes in Eastern North Carolina (Poster Abstract)

Little information is available for home range size and habitat use of northern bobwhites (Colinus virginianus) on modern agricultural landscapes in autumn. Therefore, we monitored radiomarked bobwhite coveys from September–December 1998 on farms in Wilson and Tyrrell counties, North Carolina. The Tyrrell County farm was a 6084-ha area recently developed for commercial production of corn and soybeans. Dispersed throughout crop areas were forested and fallow blocks at differing stages of succession. The Wilson County farms had small fields (x̄ = 1.8 ha, SE = 0.12) planted in cotton, soybeans, corn, and tobacco and were surrounded by mixed pine and hardwood blocks of differing ages. Mean home range size at the Tyrrell County farm was 33.2 ha (range 4.5–128.5 ha) (n = 10). The two largest home ranges, 70.7 and 128.6 ha, were disproportionately large due to large movements from harvested crop fields to permanent forested cover. Covey home ranges were not established at random (l = 0.124; x2 4= 20.18; P \u3c 0.001). Road and canal edges were selected significantly more than any other habitat followed in rank by soybean fields, corn fields, forested, and fallow blocks. Road and canal edges provided necessary cover for moving between habitat types, especially from forested and fallow blocks to crop fields. Within home ranges, coveys did not allocate their time at random (l = 0.336; x2 4 = 10.89; P \u3c 0.05). Habitats were ranked in the order of forested blocks, fallow areas, soybean fields, road and canal edges, and corn fields, but no significant differences were found between habitats. In Wilson County, average covey home range was 17.4 ha (Range: 4.9–37.6 ha)(n = 11). Coveys did not establish their home range at random (l = 0.407; x22 = 9.87; P \u3c 0.05), selecting forested blocks over crop fields (T9 = 3.02, P \u3c 0.012). Within home ranges coveys did not allocate their time at random (l = 0.1319; x25 = 22.28; P \u3c 0.001), utilizing primarily forested blocks followed by cotton fields, soybean fields, corn fields, and other areas. On both study areas, forested and fallow blocks were the only source of cover to spend time in after crop harvest. Covey use within forested and fallow blocks was concentrated along edges of crop fields, leaving large portions of this habitat type unused. Forested and fallow blocks were primarily used as loafing cover in between feeding periods in adjacent crop fields

Factors Influencing Early Morning Covey Calling in Northern Bobwhites (Oral Abstract)

Data from early morning covey calling may be useful for measuring abundance of northern bobwhite (Colinus virginianus). However, critical assumptions about detection rates, survey timing, and seasonality effects have not been tested. Additionally, the effects of weather and covey density on call rates are unknown. We quantified call rates of 219 radiomarked coveys at 5 sites in 1998 and 2 sites in 1997 and 1999 to monitor calling behavior of bobwhite coveys. First calls for coveys (n = 442) occurred on average 23.4 (SE = 0.5) min before sunrise and averaged 31.4 +- 1.9 calls/covey. Few first calls (13%) occurred after 15 min before sunrise. Across sites, call rates averaged 58% (SE 2.0) (n = 763). Call rates were most variable during September and December biweekly periods and least variable during late October and early November biweekly periods. We developed 15 logistic regression models from data collected in 1998 for predicting the probability of a covey to call. Selected best models were chosen using the Akaike information criterion modified for overdispersion and small sample size. The selected best model included number of adjacent calling coveys, wind speed, cloud cover, and barometric pressure change. Parameter estimates for number of adjacent calling coveys had an odds ratio of 1.4; the 95% CI did not contain 0. A less parsimonious model, which also included biweekly period and interaction terms, was equally as likely (QAICc 0.32) as the selected model. The 16–31 October biweekly period had an odds ratio of 1.8; conditional 95% CI not containing 0. A post hoc analysis was conducted using the same candidate model list, but we replaced number of adjacent calling coveys with deviations of the number of adjacent calling coveys from site means. Results were similar to the previous analysis with the same selected best model, but model fit was improved. Selected best models were tested using observations collected in 1999 from 2 of the 5 sites monitored in 1998. Predicted call rates were relatively precise (observed call rate-predicted call rate \u3c 0.10) for biweekly periods associated with peak call rates, but call rates were less precise (range 0.12–0.27) for other biweekly periods. Constancy of call rates suggests that at bobwhite densities we observed (0.75 and 5 bobwhites/ha), covey call surveys have potential to index fall populations of bobwhites with reasonable accuracy

Brain Cholinesterase Depression and Mortality of Bobwhite Chicks Exposed to Granular Chlorpyrifos or Fonofos Applied to Peanut Vines

Granular-formulated insecticides are applied on over 60% of the peanut acreage in North Carolina, each year, to control southern com rootwonn. This application is applied as a 0.45m band overtop peanut vines between June and August. Lorsban® 15G (chlorpyrifos) and Dyfonate® 15G (fonofos) are used 90% of the time by peanut growers. Quail chicks foraging within or on the edge of peanut fields may consume granules as grit material as the insecticide granules are not soil-incorporated. Therefore. we examined the hazard posed by these insecticides to bobwhite chicks foraging in peanut fields. Two identical experiments were conducted in which 4, 15X!50m plots, were treated with Lorsban 15G or Dyfonate 15G and 2 plots were untreated. Human-imprinted bobwhite chicks (N = 7-9 chicks per plot) from two age groups, 4-7 or 11-12 days, were allowed to forage for one hour in treated and control plots. Brain cholinesterase (ChE) activity and ChE depression, relative to control ChE values, were determined for each chick. Differences in ChE activity between treatments were tested for using a two-way ANOVA with broods serving as the experimental unit. Relationships of age to ChE depression, within treatments, were analyzed separately using linear regression. Chicks foraging in peanut fields were observed ingesting granules directly and indirectly via granules adhered to arthropods. Chick brain ChE depression averaged 22% (SE = 3.6) and 8% (SE = 3.2) for chicks exposed to Dyfonate and Lorsban, respectively. Brain ChE was significantly lower than control values for chicks exposed to Dyfonate (P = 0.014 ). While ChE depression was not correlated to chick age (P \u3e 0.15), two 4-day-old quail chicks exposed to Dyfonate died and one 7-day-old chick was unable to walk. Chicks exposed to Dyfonate were lethargic and brooded whereas chicks exposed to Lorsban and control chicks showed no overt behavioral changes. Our results indicate that this application of Lorsban 15G presents a relatively low hazard to quail chicks foraging in recently treated peanut fields. In a follow-up experiment, chicks foraging in Dyfonate-treated peanut fields, I day post-application, exhibited less ChE depression (x = 12%, SD = 10.2) than chicks exposed immediately following the application, suggesting the hazard from Dyfonate may be temporary

Exposure of Captive Bobwhites to an At-Planting Application of Terbufos (Counter 15G) to Corn

Terbufos is a highly toxic, organophosphate insecticide that is commonly applied to com fields during planting. Quail use crop field edges during April, when com is planted in North Carolina, and consequently may be exposed to at-planting insecticides. Therefore, we attempted to quantify the hazards to quail from an at-planting, banded application of Counter® 15G using penned northern bobwhite quail. Eight, 7.5 X 7.5m pens were placed in cornfields immediately after planting. Six field pens received Counter 15G at 22.7g per IOOm of cornrow. Pens were placed such that a 2.5 X 7.5m section was located in standing wheat. The remainder of each pen extended past the turnrows into a section of regular rows in each cornfield. Two quail of each sex were placed in each pen. Behavior of quail using cornfields was observed from blinds and categorized as feeding, loafing, dusting and other. Blood serum, for determining cholinesterase (ChE) activity, was collected from a sub-sample of quail (n = 3) from each pen prior to and at 1.5, 8.5 and 15.5 days following exposure. Change in (ChE) activity from pre-exposure levels was determined and averages for birds from each pen were compared between treatments using a one-way analysis of variance. In quail exposed to terbufos, serum ChE activity declined 21% relative to pre-exposure levels at 1.5 days (P = 0.04; df = 1,4), but not at later dates sampled (P \u3e 0.08). No mortality was observed. Observations of quail in pens revealed no unusual behaviors or changes in behavioral patterns over the course of the study. Our results suggest that Counter® 15G is unlikely to cause mortality or significant behavioral changes in wild quail inhabiting farms

Efforts to Enhance Stakeholder Communications in North Carolina\u27s Wildlife Damage Control Agent System

In 1995, North Carolina Wildlife Resources Commission (NCWRC) established policy and rules for handling of nuisance wildlife by Wildlife Damage Control Agents (WDCA). The policy required a one-day long training session, culminating in an open book, certification examination. The North Carolina Cooperative Extension Service (NCCES) conducted the training and administered the examination. The certification-training program covered principles of wildlife damage management, wildlife laws and regulations, humane handling of animals and euthanasia, human health risks from exposure to wildlife, professional ethics, and sources of technical information. Between October 1995 and March 2000, 7 certification-training sessions were held and 289 WDCA\u27s were certified, with agents in 57 of 100 counties. The Wildlife Division of NCWRC administrated the program. WDCA\u27s are entitled to issue Wildlife Depredation Permits to North Carolina residents suffering damage from native wildlife that are not specially protected by federal or state laws. The depredation permit provides for the listing of the issuing WDCA as a second party to the permit. While there is no charge for the permit, the WDCA can charge for removal of the animals and repair of structures. WDCA\u27s must be re-certified every 3 years. The WDCA program was evaluated by surveying the first group of 47 agents, certified in 1995, when they completed their examinations for recertification in 1998. Additionally we surveyed wildlife enforcement officers, district wildlife biologists and their supervisors, and cooperative extension agents to gain their views of the WDCA program. No major problems were reported with program administration or training . The cooperative relationships among leading and supporting agencies were excellent. Increased effort at WDCA publicity, both locally and statewide were recommended. In 2000, the pamphlet, The North Carolina Wildlife Damage Control Program was written and published. The pamphlet was distributed to county extension centers, wildlife law enforcement officers, USDA-Wildlife Services staff, and NCWRC centers, wildlife law enforcement officers, USDA-Wildlife Services staff, and NCWRC wildlife biologists. NCWRC now lists all the WDCA who wish to work with the public on their website, http://www .wildlife.state.nc.us/. Extension agents have been encouraged to hold meetings of WDCA, Wildlife Law Enforcement Officers, and NCWRC biologists in their counties to encourage better communications

Effects of Field Borders and Mesomammal Reduction on Northern Bobwhite and Songbird Abundance on Three Farms in North Carolina (Oral Abstract)

Lack of early nesting habitat may be limiting population levels of northern bobwhites (Colinus virginianus) and early successional songbirds on agricultural landscapes. Alternatively, detrimental effects of mesomammal predators on nesting success and survivorship of bobwhites may be causal at low densities. Previous research has documented increased use of agricultural areas by bobwhites on farms with field borders, but bobwhites had low nesting success in these areas. No replicated studies in the southeast United States have been conducted investigating the effects of field borders and mesomammal predator reduction on bobwhite and songbird abundance. We conducted a 3-year study on farms in Hyde, Tyrrell, and Wilson counties, North Carolina using a 2 x 2 factorial treatment combinations and a blocked study design. On each study area, 4, 200-ha farm blocks were randomly assigned 1 of 4 treatments. Treatments included: (1) 5–10 m fallow vegetation borders on all disked field edges, (2) removal of mesomammal nest predators (raccoons (Procyon lotor), opossums (Didelphis virginianus), and foxes (Urocyon cinereoargenteus and Vulpes vulpes)) between January through June of each year, (3) a combination of field borders and predator reduction, or (4) neither treatment. In 1997–99, we measured fall abundance of bobwhite coveys on farm blocks using morning covey call surveys and summer abundance of songbirds using variable radius point counts. Field borders were established in 1996 in Hyde and Wilson counties and 1997 in the Tyrrell county study area. Number of mesomammal predators annually removed from farm blocks averaged 42 (SE = 3.5) and was similar between study areas and years. Field border farm blocks had consistently more coveys heard than non-border farm blocks (F1,2 = 216.0, P \u3c 0.004). However, there were no differences in the number of coveys heard between predator reduction and non-reduction farms (F1,2 =10.4, P = 0.084). Farms with both field border and predator reduction had more coveys heard compared to other farm blocks (F1,2 = 43.3, P \u3c 0.0223). Summer bobwhite abundance was greater on field border areas (F1,6 = 5.93, P \u3c 0.051). No other differences in songbird abundance were detected between field border and non-border farms. In 1997, songbird nest density was estimated in field border and non-border farms on the Wilson County study area. Field border farms had higher nest density, particularly for field sparrows (Spizella pusilla) and common yellowthroats (Geothlypis trichas), and had greater nesting bird diversity. Field borders were a practical technique to increase bobwhite abundance on small farm blocks. Increases in bobwhite abundance associated with predator reduction on small farms with field border would not be economically feasible in most circumstances

Effects of Filter Strips on Habitat Use and Home Range of Northern Bobwhites on Alligator River National Wildlife Refuge

Lack of breeding habitat for northern bobwhites (Colinus virginianus) on agricultural landscapes is a factor that limits populations. Therefore, we examined how the addition of filter strips around crop fields and along crop field drainage ditches impacted northern bobwhites. Our study focused on habitat use, home range and brood-rearing range of bobwhites, from April through September I 993-94. Two farms on Alligator River National Wildlife Refuge were sub-divided into filter strip (FS) and non-filter strip (NFS) sections. More bobwhites were found on FS sections than on NFS sections based on flush counts (4.3x more on FS areas: P = 0.02). We used log-linear analysis to examine the distribution of telemetry locations (n = 1796) of radio-marked bobwhites (n = 218) across 5, 4.6m bands parallel to drainage ditches. Bobwhite locations were skewed towards ditches, particularly on FS sections before soybeans matured to a size that was sufficient to provide canopy cover for bobwhites. Bobwhites captured on FS sections had significantly smaller breeding season ranges than those captured on NFS sections (P = 0.001). Adult and sub-adult breeding season (May-Aug) ranges (n = 23) averaged 32 ha (SE = 26) and 182 ha (SE = 41) on FS and NFS sections, respectively. Brood ranges to 14 days (n = 9) ranged from 0.8 ha to 2.2 ha depending on habitat and calculation method. Presence of filter strips shifted habitat use patterns, especially during spring and early summer, and improved crop fields as habitat for breeding bobwhites