Determining the risks associated with scavenging raptors to the biosecurity of broiler farms on Delmarva.

Determining the risks associated with scavenging raptors to the biosecurity of broiler farms on Delmarva.

Summary

Vultures dig into broiler mortality composters on commercial broiler farms to gain access to the mortality. This is a significant biosecurity risk given the density of broiler production here on Delmarva. Producers have expressed frustration and concern at the situation. Vulture numbers vary on each farm, but the factors that influence the numbers have never been studied. Poultry farmers nationwide have mentioned that vultures dig in their composters yet no patterns of behavior have been identified.

            There are two species of vulture on Delmarva: Black Vultures and Turkey Vultures. To gather more information on the scavenging raptors we propose to teach 15 broiler producers to scout (ID and count) on their farms at the composters for 15 minutes weekly for one year. Second, we will place game cameras on 10 broiler farms at the composters to determine which species of scavenging raptors are actually breaching the piles and removing the carcasses.

The farmers, in their frustration, have commented that they would prefer to shoot the birds, which would perhaps deter them from visiting composters. After a survey, it is clear that broiler farmers in the region do not know very much about the federal laws regarding wild birds, which includes vultures. A change to the nutrient management curriculum to include information on vultures is proposed in this project. Farmers are required to attend continuing education courses to earn nutrient management credits. This is a good venue for educating farmers about the ecology and behavior of scavenging raptors on their farms. Outreach will be in the form of participants speaking at local farm meetings, a fact sheet and journal article.

Objectives/Performance Targets

Scouting Study:

We trained 10 broiler producers to scout, identify and count vultures at the composters for 5 minutes three times a week. This scouting is taking place from June 2014 to March 2015. We provided producers with a journal into which they will place their data and recordings. The journal contains a raptor ID sheet to assist producers in making accurate identifications. Also, general weather observations are included in the journal.

            The scouting skills were taught to the producers by the extension agents involved in the project. Using the outreach methods currently in place on Delmarva, producers were asked if they are interested in participating in the study. Ten farmers showed an interest and agreed to participate in the scouting study. The farmers send in their scouting data to the researchers on a monthly basis. The data is being input by a student and analyzed by the extension poultry specialists.

            When the extension poultry specialist visits with the producers on their respective farms, they assessed the quality of the composter prior to teaching scouting skills. Using a temperature probe as well as accepted visual assessment techniques, the compost management was rated. The ratings were either good, average, or poor. Once the scouting period is finished, the composter on each farm will be assessed using the same techniques in order to determine if there has been any improvement. It is expected that farmers, by spending more time near the composting area, will improve their composter management, if needed. In addition to the data collected from scouting, we will, at the end of the study in 2015, ask farmers to complete a post-experiment form to provide constructive criticisms and suggestions about how the project could have been done better, and to indicate what went well.  

 Curriculum Change:

The curriculum has been added to the already well-established waste management and compost management programs presented by both the Maryland and Delaware extension poultry specialists. Broiler producers are required to obtain continuing education credits to maintain their nutrient management certification. The new curriculum includes information on bird ecology and also the laws regarding migratory bird species. The data obtained from the scouting and game cameras will be presented at grower meetings throughout Delmarva.

In March 2014 we obtained the equipment and placed them on farms (Dr. McCrea). Also in March, we notified members of Delmarva’s broiler industry of our project through email, Facebook, listserves, face-to-face meetings, telephone calls, and workshops (Dr. Moyle & Mr. Brown). We sought participatory farms for scouting (trial 1) and also for placing game cameras (trial 2).

Accomplishments/Milestones

There are a total of 10 farmers who were interested in participating in the scouting surveys.  We have asked that surveys be returned via mail monthly and have been receiving surveys.  A student has been hired to input survey data and also game camera data.  Game cameras have been placed at 5 locations. The study is ongoing (scouting surveys and game camera data) with projected completion in March 2015. 

One newly created broiler field day, held on October 31, 2014, was attended by 250 broiler farmers and both Drs. McCrea and Moyle, as well as Mr. Brown and the student, were in attendance to answer questions about the project.  A poster about the project was on display at the field day and the results to date were discussed with broiler farmers. 

On January 16, 2015, Dr. Moyle will present preliminary data from the project to farmers at the 2015 Delaware AgWeek Commercial Poultry Session. This is an all-day event aimed at providing information to growers on topics both timely and pertinent to their operations.

An abstract for a poster on vultures at Delmarva composters has been accepted for presentation at the International Poultry Scientific Forum to be held in Atlanta, GA on January 26-27, 2015.

Impacts and Contributions/Outcomes

Farmers who attended the broiler field day indicated that they learned a great deal at the event.  At the event, farmers were asked to respond, by a show of hands, if they had learned about the time of day and species of vultures seen in the study.  All of the 150 persons who visited the vulture control station at the broiler field day event indicated that they learned more about the species of vulture, their behavior, and what times of day they are most likely to see them. Farmers did ask about differences between the two species of vultures and explanations were provided.  Farmers were asked if they employed mitigation strategies, and for the few farmers who had experienced Vultures at their composters, most did not have any way to exclude the pests.  It is now understood that any changes made to a composter, such as adding lids to exclude vultures, is not permitted by the Department of Natural Resources and Environmental Control, however a display at the field day demonstrated the effectiveness and functionality of adding lids to composters.  Presentations at additional broiler farmer events are planned for the winter and spring of 2015, as is the development and distribution of a fact sheet.

Collaborators: