Camera Trap Reconnaissance of Wildlife in the Napatree Point Conservation Area: Sampling

Camera Trap Reconnaissance of Wildlife in the Napatree Point Conservation Area: 2016-2017 Sampling Peter August 1, Janice Sassi 2 & Scott Rasmussen 1 1 Department of Natural Resources Science, University of Rhode Island 2 Napatree Point Conservation Area, Watch Hill Conservancy & Watch Hill Fire District INTRODUCTION: The western end of Napatree Point consists of a variety of ecological communities maritime shrubland, salt scrub, maritime shrub dune, high marsh, maritime herbaceous dunes, rocky shore, and maritime beach. Previous years of camera trapping have shown that the mammal fauna of this section of Napatree is surprisingly diverse. The mammals of Napatree play an important role in the ecosystem and serve as predators, prey, plant consumers, and seed dispersers. The overall purpose of our camera trap survey is to assess the diversity and relative abundance of mammals (and occasionally birds) in the different habitats in the Napatree Point Conservation Area (NTPCA), Watch Hill, RI. This is the fifth year we have been camera trapping at Napatree and each year we strive to monitor different habitats in the Conservation Area. We have also established a long-term benchmark site to allow us to track changes in animal abundance across years. These data will contribute to the overall ecological knowledge of the NTPCA, serve as a baseline inventory of mammals of Napatree, and provide objective data on the relative abundance of potential predators of shorebirds in the area. With these baseline data on predator populations, we are beginning to discern trends in the relative abundance of various species on Napatree. METHODS: We deployed camera traps (Reconyx Rapid Fire) in multiple locations in the Napatree Point Conservation Area to monitor animal activity (Figure 1). Five locations were sampled in the 2016/2017 monitoring season and are described in Table 1. At each site, a camera was set approximately 1 m off the ground on a tripod, affixed to a stout branch, or mounted on a wooden pole. The SD card containing photographs was retrieved on a 2-8 week interval. The camera ran continuously during the period of deployment and was set to record five consecutive photographs every time the motion sensor beam was broken. Each photo was stamped with the date, time, temperature, moon phase, and which shot in the five-photo sequence it was. Photos taken in the day were color and photos taken at night were black and white and were illuminated by an infrared flash. For data analysis, an animal that was continuously present for a string of consecutive photos was recorded as a single occurrence (visit). When photo sequences were more than 5 minutes apart they were counted as separate animal visits.

Figure 1. Camera trap sampling locations in 2016-2017.

Site Sampling Period Total Days of Camera Sampling Habitat Pines 25 Oct 2016 12 Dec 2016 Log 23 Oct 2016 11 May 2017 Dune Log 16 Dec 2016 26 Jan 2017 Herp Edge 26 Jan 2017 1 Mar 2017 Phrag Field 1 Mar 2-17 11 May 2017 50 The stand of Japanese Pines in the southwest corner of the Lagoon. 148 Along a large log at the edge of a Phragmites patch and shrubland. 39 Along a large log in the middle of the dune grass. 35 On the edge of the shrub woodland and grassy open field. 68 In a dense stand of Phragmites in a low, sometimes slightly flooded (< 10 cm deep) area. Table 1. Camera trap sampling habitats in 2016-2017. RESULTS: The species captured and capture frequency are given in Table 2. A new species of mammal for Napatree was added this year, a domestic cat passed through the Pines. The presence of people and domestic dogs was higher this year than previous years but this is a result of the public settings (Pines, Dune Log) of some of the camera traps. Predator abundance at the Log was the lowest in the last three years of camera trapping (Figure 2). It unclear whether this reflects a decrease in predators on Napatree or a change in the habitats they are using. The patterns of species occurrence and abundance were consistent with preceding year s camera trapping. Mammal diversity and abundance in the dunes is low except for mice. Rabbits are most abundant at the edge of shrub and grassy habitats (e.g., The Pines, Herp Field). Deer continue to be very common west of the Lagoon.

Location Total # Visits Recorded (Visits/100 Days Sampling Effort) Species Common Name Pines Dune Log Log Herp Edge Phrag Field Didelphis virginiana Virginia Opossum 2 Homo sapiens Human 9 1 (18.0) Sylvilagus floridanus Eastern Cottontail 14 Rabbit (28.0) Peromyscus sp. Deer Mouse 1 (2.6) Canis latrans Coyote 1 2 (1.3) 3 10 (29.4) Canis familiaris Domestic Dog 1 2 (5.2) Vulpes vulpes Red Fox 1 1 (0.7) Neovison vison Mink 1 Mephitus mephitus Striped Skunk 1 Odocoileus virginianus White-tailed Deer 8 (5.4) Felis catus Domestic Cat 1 Misc Birds 2 1 (5.2) (0.7) 1 1 6 (8.8) 2 7 (10.3) 13 (19.1) Table 2. Species recorded in the 2016/2017 sampling period. The total number of visits per species and the frequency of visits (in visits/100 camera trap days) are reported.

Figure 2. Predator abundance at the Log location for three years. CONCLUSIONS: Predator numbers at the Log were quite low in the 2016/2017 camera trapping season; however, coyote, mink, and fox were recorded in other camera trap locations, albeit in low numbers. It will be interesting to see if this trend continues. As in previous years, deer were frequently photographed. This year we obtained many photos of deer in their Spring molt. As in previous years rabbits were regularly photographed in a diversity of habitats. DATA MANAGEMENT: Photographs are stored in a DropBox folder. Annual tallies are stored in NP_Data/Biological/Photos/CameraTrap ACKNOWLEDGEMENTS: This project was supported by the University of Rhode Island Coastal Institute, the USDA Renewable Resources Extension Act, the URI College of the Environment and Life Science Extension Program in Natural Resource Conservation and Management, and the United States Fish and Wildlife Service.

Appendix 1. Representative photos from the 2016/2017 camera trapping season Deer at the Log site Deer in Spring molt Coyote at the Phrag site

Mink in the Pines Domestic cat at the Pines Fish Crow taking flight. Note the tail feather that has fallen out underneath the bird.