Northeastern Naturalist Vol. 25, No. 1 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 87 2018 NORTHEASTERN NATURALIST 25(1):87–100 Monitoring of Dung Beetle (Scarabaeidae and Geotrupidae) Activity Along Maryland’s Coastal Plain Patrick Simons1, Michael Molina1, Mallory A. Hagadorn2, and Dana L. Price1,* Abstract - Our understanding of how human activities impact insect communities is limited. Dung beetles, well known for the ecosystem services they provide, are faced with many conservation threats, particularly from deforestation and agriculture. Here we used 200-m transects and human-dung–baited pitfall traps to examine dung beetle populations in 7 forests of Maryland’s Coastal Plain. We set traps once a month, from May 2014 to April 2015, to determine species presence, abundance, range, and seasonality. We collected 6463 individuals representing 22 species; Janes Island State Park (JISP) had the highest abundance (2705 individuals) and Martinak State Park (MSP) had the highest species richness (19 species). During summer 2015, we examined the succession of dung beetles attracted to bait in JISP and MSP. We set 10 traps once a month (May–August) in each site and collected beetles on days 1, 3, 5, 7, 14, and 21 without dung replacement. In JISP, Onthophagus hecate (Scooped Scarab) was abundant throughout each 21-d period, and accounted for 68% of all beetles collected. In MSP, most specimens were collected by day 5. Here we provide information for conservation of locally rare or uncommon species. Introduction The Atlantic Coastal Plain is the largest physiographic province in Maryland, with the Piedmont/Coastal Plain fall line crossing through the northeastern tip of the state (Edwards 1981). Maryland’s Eastern Shore, east of the Chesapeake Bay and Elk River, consists of 9 counties, which make up 32% of the state’s land area. This region is characterized by a flat, low-lying landscape, with elevations usually less than 18.3 m (60 ft) above sea level (MSWAP 2015). In geological terms, Maryland’s Eastern Shore consists of unconsolidated sediments of gravel, sand, silt and clay, and represents the youngest region of the state (Edwards 1981). For 6000 years, the modern vegetation of the area changed very little, yet with the increase in human population in the 1800s, people cut large swathes of forest to support shipbuilding, paper pulp, and iron manufacture, and increased agriculture (Brush 2008). By the early 1900s, 60–80% of the Chesapeake Bay watershed was deforested and under cultivation (Brush and Hilgartner 2000). As the Great Depression swept the US, farms were abandoned, and human populations shifted to urban areas (Brush 2008, Kays 1995). Former agricultural lands reverted to Pinus (pine) and hardwood forests, which comprises most of the Eastern Shore’s modern forest cover (Kays 1995). Area of impervious surfaces increased and forests became fragmented as urbanization continued (Brush 2008). Today, forest cover varies from 35% to 51%; 1Department of Biological Sciences, Salisbury University, Salisbury, MD 21801. 2Department of Biology, Utah State University, Logan, UT 84322. *Corresponding author - dlprice@salisbury.edu. Manuscript Editor: Ralph Grundel Northeastern Naturalist 88 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 Vol. 25, No. 1 forests are dominated by Quercus (oak)–Carya (hickory) and oak–pine, the latter prevailing in the southernmost counties (Kays 1995). Through the urbanization process, many of the large-mammal species that historically inhabited this area became regionally extinct. Puma concolor L. (Cougar), Ursus americanus Pallas (American Black Bear), Canis lupus L. (Grey Wolf), and possibly Bison bison L. (Bison) formerly occurred on Maryland’s Eastern Shore, but could not persist following human population growth and development (Scott 1991, Sipple 1994). Today, the large terrestrial mammal fauna is limited to Odocoileus virginianus Zimmerman (White-tailed Deer), Cervus nippon Temminck (Sika Deer), Procyon lotor L. (Raccoon), Canis latrans Say (Coyote), Vulpes vulpes L. (Red Fox), and Urocyon cinereoargenteus Schreber (Gray Fox). Many of the habitats where these animals thrive are the same as those valued for recreation and other human activities (Brofman 2015). We need to assess the major threats to wildlife in this region and determine how to maintain animal populations in an ecological manner, but one that also supports recreational activities and other human interests (MSWAP 2015). Dung beetles (Coleoptera: Scarabaeidae and Geotrupidae) are extremely beneficial in forest habitats where their feeding and burial of dung promotes nutrient cycling and maintenance of key ecosystem processes (Nichols et al. 2008, 2009). These beetles are also known to be excellent indicators of biodiversity (Gardner et al. 2008; Larsen 2007, Larsen 2011, Spector 2006) and environmental health (Davis et al. 2001, Feer and Hingrat 2005, McGeoch et al. 2002, Nichols and Gardner 2011). Thus, regional decline in mammal fauna can disrupt the diversity and abundance of dung beetle communities, with significant short- and long-term implications (Nichols et al. 2009). In many ecosystems, dung is an ephemeral resource, which makes competition for this microhabitat intense (Hanski and Cambefort 1991). Assessment of environmental threats to dung beetle biodiversity and establishment of land-management practices for conservation of these communities is of critical importance. Here we examine dung-beetle activity in 7 forests along 150 km of Maryland’s Eastern shore. With the exception of dung beetles collected from cattle farms (M.A. Hagadorn et al., unpubl. data), very little is known about Maryland’s dung beetles (Price et al. 2012, Rentz and Price 2016). Herein,we provide data on diversity and abundance, seasonal activity, and range of forest-dwelling dung beetles, and examine the succession of these beetles attracted to a limited food resource. We assessed dung beetle communities, as a whole, to better understand the unique ecosystem in which they live and provide data to suggest that several species are locally rare or uncommon. Field-site Descriptions We sampled dung beetles in 7 forests along Maryland’s Eastern Shore (Fig. 1)— Sassafras Natural Resource Management Area (SNRMA), Tuckahoe State Park TSP), Martinak State Park (MSP), Seth Demonstration Forest (SDF), Henson Scout Reserve (HSR), Showell Conservation Easement (SCE), and Janes Island State Park (JISP) (Table 1). We obtained permits for collection of beetles in the 5 parks that are Northeastern Naturalist Vol. 25, No. 1 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 89 owned and managed by the Maryland Department of Natural Resources (MDNR). We also obtained permission for collections in the Henson Scout Reservation and Showell Conservation Easement (owned by Maryland Coastal Bays Program). Methods Diversity collections In order to examine dung beetle species richness and abundance, we used 200-m linear transects, with human-dung–baited pitfall traps (Larsen and Forsyth 2005), set every 50 m (5 total for each site). Human dung is among the most attractive baits to most species of coprophagous beetles (Howden and Nealis 1975) and is a readily available resource. Traps consisted of a 2.4-L (2.5-qt) plastic container (16 cm diameter, 15 cm depth) buried in the soil, flush to the rim. We hung mixed human dung, wrapped in cheesecloth and tied with biodegradable twine, from mesh chicken wire placed over the bucket.. We placed a 20 cm x 20 cm plywood tile at a 45o angle above the trap to prevent rainwater flooding. We added a small amount of water and table salt to the bottom of each bucket to preserve the specimens until collection. We baited the traps once a month (May 2014–April 2015) for a 7-d period. We placed all collected beetles in 75% ethanol and returned to the lab for sorting and identification. We calculated estimated species richness (Chao1, ICE, and ACE richness metrics) in EstimateS version 9.1.0 software (Colwell 2013). We created species-accumulation curves to illustrate the rate at which new species were sampled and examined rarefaction curves to compare species richness among the 7 forests (Gotelli and Colwell 2001). We examined species diversity using the Shannon exponential mean (eH) and Simpson’s index (1/D). Figure 1. Location of 7 forests along Maryland’s Coastal Plain region. Site locations are listed north to south in Table 1. Northeastern Naturalist 90 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 Vol. 25, No. 1 Table 1. Dung beetle collection sites (north to south), latitude/longitude, hectares, forest coverage, and soil type. MDNR = Maryland Department of Natural Resources. Latitude/ Location (owner/manager) Acronym Longitude Forest size Forest cover Soil type Sassafras Natural Resources Management SNRMA 39°20'46.52"N 401 ha Deciduous tree cover; woodlands Silty loam Area (MDNR) 75°59'12.91"W surrounded by agricultural land and wetlands. Tuckahoe State Park (MDNR) TSP 38°57'56.26"N 1590 ha Fragmented forest (including a 24 ha Sandy loam 75°56'39.53"W manmade lake); mixed pine and hardwoods surrounded by agricultural land; open to camping and equestrian activities. Martinak State Park (MDNR) MSP 38°51'43.92"N 42 ha Mixed hardwood and coniferous forest; Sandy loam 75°50'16.52"W subject to camping and visitation Seth Demonstration Forest (MDNR) SDF 38°44'51.81"N 49 ha Deciduous forest surrounded by both Silty loam 76°2'3.35"W agricultural land and suburban residential areas; open to public bow hunting. Henson Scout Reserve (HSR) HSR 38°32'43.98"N 760 ha Mixed deciduous and pine forest Sandy loam 75°45'10.80"W (mostly Pinus taeda L. [Loblolly Pine]); the Boy Scout reservation managed by the Del-Mar-Va council BSA. Showell Conservation Easement (SCE: SCE 38°23'52.99"N 32 ha Deciduous forest; the area is a former. Silty clay loam Maryland Coastal Bays Program) 75°13'25.69"W agricultural property that is under restoration to become contiguous forest Janes Island State Park (MDNR) JISP 38° 0'35.25"N 178 ha (+ Mostly coniferous forest dominated by Silty hydric clay 75°50'36.77"W 1100 ha of Loblolly pine; coastal park of the saltmarsh Chesapeake Bay dominated by salt marsh habitat) habitat (1100 ha).; open to camping, hiking, and kayaking. Northeastern Naturalist Vol. 25, No. 1 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 91 Succession To determine the succession of dung beetles attracted to dung bait, we followed methods similar to Sabu et al. (2007) and Rentz and Price (2016) to collect beetles. This method allowed us to determine when beetles were attracted to the bait, and if possible, to capture additional species with an extended collection period. We set 10 pitfall traps (as described above) at 2 sites: MSF and JISP (Table 1). We randomly placed traps at least 50 m apart to avoid interference with other traps (Larsen and Forsyth 2005). We baited the traps with 50 g of mixed human dung once a month (May–August 2015) and collected beetles after days 1, 3, 5, 7, 14, and 21 days without replacement of bait. We preserved specimens in 75% ethanol for later sorting and identification. We pinned/pointed specimens of rare species and placed them in the DLP Entomological Collection at Salisbury University, Salisbury, MD. Results Species diversity and richness Dung-beetle species richness was highest in MSP (19 species and 1218 individuals collected) and lowest in TSP (10 species and 203 individuals collected) (Tables 2, 3). JISP had low species richness (11) , yet the highest abundance of all sites: 2705 individuals collected (Tables 2, 3). The estimated species richness for the sites varied from 11 to 22 species (Table 2). Sample-based species-accumulation curves demonstrate that we collected 80% of the species after just 8 samples (Fig. 2). All sites need further sampling, with the exception of JISP which reached an asymptote by sample 10 (Fig. 2); all richness indices for JISP corroborate these findings (Table 2). Rarefaction curves suggest there is high variation in community structure among the different forests (Fig. 3). Both MSP and SNMRA had high species-richness and low density; JISP had extremely high density and was omitted from the rarefaction analysis (Fig. 3). Species diversity (eH and 1/D) was similar among all sites, varying from 2.71 to 5.61 (Table 3). Table 2. Species richness, abundance, and diversity of dung beetles collected from 7 forests of Maryland’s Atlantic Coastal Plain. ICE = incidence-based coverage estimator of species richness and ACE = abundance-based coverage estimator of species richness. See Table 1 for location acronyms. Location SNRMA TSP MSP SDF HSR SCE JISP Species richness 11 10 19 13 12 12 11 Abundance 308 203 1218 494 518 1017 2705 Estimated species richness Chao 1 19.00 10.66 21.25 15.00 12.50 12.00 11.00 ICE 14.36 12.64 22.41 14.15 14.08 14.22 11.00 ACE 15.82 11.90 21.57 14.30 12.48 12.30 11.00 Species diversity Shannon exponential mean (eH) 3.47 4.93 5.61 4.34 5.29 4.53 4.72 Simpson’s index (1/D) 2.71 4.12 3.58 2.78 4.25 3.75 3.26 Northeastern Naturalist 92 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 Vol. 25, No. 1 We found the indigenous species Copris minutus (Small Black Dung Beetle), Geotrupes blackburnii (Blackburn's Earth Boring Beetle), and Onthophagus hecate (Scooped Scarab) at all 7 sites; these were the 3 most abundant species overall, with 816, 2048, and 1966 individuals collected, respectively. We also collected another indigenous species, Onthophagus pennsylvanicus, in all 7 forests, but in low numbers, with the exception of JISP (345 individuals). Species captured in abundance in only 1 or 2 forests include Irrasinus stupidus (MSP and HSR), Canthon viridis (SDF and TSP), and Onthophagus concinnus (MSP and SCE). Geotrupes splendidulus was only collected in SDF. We collected 1 specimen of Copris fricator from SNRMA, the northernmost forest, and 2 specimens (1 in TSP and 1 in MSP) of Onthophagus subaneus. Both C. fricator and O. subaneus had previously only been reported from counties west of the Chesapeake Bay (Staines 1984). Seasonality of beetles was similar in all 7 forests, though not all species were present in all forests (Tables 4). In general, Geotrupes blackburnii was most abundant March–May, and again from October–December (Table 4). Abundance was highest for Canthon chalcites, Onthophagus hecate, and O. pennsylvanicus during May–August, for G. egeriei (Eger's Earth Boring Beetle) in July–September, and for Copris minutus during August–November (Table 4). Table 3. Dung beetles collected from 7 forests of Maryland’s Atlantic Coastal Plain. See Table 1 for location acronyms. Location Family/species SNRMA TSP MSP SDF HSR SCE JISP Total Scarabaeidae (Aphodiinae) Alloblackburneus rubeolus (Palisot de Beauvois) - - 1 - - - - 1 Blackburneus stercorsus (Melsheimer) 3 - 6 1 - 7 14 31 Irrasinus stupidus (Horn) - - 38 - 4 - - 42 Oscarinus rusicola (Melsheimer) 1 - 11 2 8 6 61 89 Pseudagolius bicolor (Say) 4 - 43 7 3 7 50 114 Scarabaeidae (Scarabaeinae) Ateuchus histeroides (Weber) 1 - 1 - - - - 2 Canthon chalcites (Handelman) - - 3 - 62 88 118 271 Canthon viridis (Palisot de Beauvois) - 2 - 24 - - - 26 Copris fricator (Fabricius) 1 - - - - - - 1 Copris minutus (Drury) 21 35 126 37 114 220 263 816 Onthophagus concinnus Laporte - - 46 - - 2 - 48 Onthophagus hecate (Panzer) 129 56 9 89 33 295 1355 1966 Onthophagus orpheus (Panzer) 12 29 2 3 - 4 - 50 Onthophagus pennsylvanicus Harold 1 2 23 3 1 6 345 381 Onthophagus striatulus (Palisot de Beauvois) 2 6 2 26 2 - 32 70 Onthophagus subaeneus (Palisot de Beauvois) - 1 1 - - - - 2 Onthophagus taurus (Schreber) - - 3 4 - 1 2 10 Onthophagus tuberculifrons Harold - 1 238 1 3 - - 243 Phanaeus vindex Macleay (Rainbow Scarab) - - 8 - 3 18 22 51 Geotrupidae Geotrupes blackburnii (Fabricius) 133 69 573 277 190 363 443 2048 Geotrupes egeriei Germar - 2 84 - 95 - - 181 Geotrupes splendidus (Fabricius) - - - 20 - - - 20 Northeastern Naturalist Vol. 25, No. 1 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 93 Succession To determine the degree of attraction to a food resource over time, we examined the succession of beetles attracted to human-dung–baited pitfall traps during a 21-d collection period (Hanski 1980, Menéndez and Gutiérrez 1999). During May to August 2015, we collected 3777 beetle specimens, 18 species (516 individuals) from MSP (Table 5) and 9 (3261 individuals) from JISP (Table 6). In MSP, we collected 88% of the beetles by day 7 (Table 5). The 2 most abundant species in MSP were Geotrupes blackburnii, and G. egerieri. According to our seasonality data (Table 4), G. backburnii is most abundant May and June, while G. egerieri is abundant during July and August (Table 4). Copris minutus, Onthophagus hecate, O. pennsylvanicus, O. striatulus, and O. tuberculifrons were each sampled throughout the entire 21-d collection period, suggesting there is considerable competition for resources in this forest. At JISP, we collected 70% of the individuals by day 7 (Table 6). As in the diversity study, O. hecate was the most abundant species accounting for 68% (2212 Figure 2. Species-accumulation curves for dung beetles collected May 2014–April 2015, from 7 forests along Maryland’s Coastal Plain region. Locations are provided in the legend, north to south. See Table 1 for location acronyms. Northeastern Naturalist 94 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 Vol. 25, No. 1 of 3261) of the specimens collected. Oscarinus rusicola (Aphodiinae) was the only species at JISP that was more abundant after day 7, with 147 of 217 specimens collected on days 14 and 21 (Table 6). No new species were found at MSP or JISP. Discussion Species diversity MSP and TSP, located less than 15 km from one another, are both vegetated by hardwoods and mixed pines on sandy loam soils and used for camping and hiking activities. Thus, it is interesting that MSP had the highest species richness and TSP the lowest. The MSP forest site was part of a nearly contiguous 42-ha forest, bordered by the Choptank River and Watts Creek. In contrast, TSP is the largest park we investigated (1590 ha), but it is highly fragmented by agriculture, a factor that may contribute to low species richness and abundance. Figure 3. Sample-based rarefaction curves for dung beetles collected May 2014–April 2015, from 6 forests along Maryland’s Coastal Plain region. We omitted Janes Island State Park here because the abundance of beetles collected was at least twice that of all other forests, and an asymptote was demonstrated after 10 samples (see Fig. 2). Locations are provided in the legend, north to south. See Table 1 for location acronyms. Northeastern Naturalist Vol. 25, No. 1 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 95 JISP, located in the southernmost region of Maryland, is made up of 2 distinct regions: (1) a 178-ha area including campsites and forested landscape bordered by agriculture; and (2) the largest portion that is only accessible by boat (MDNR 2017). Humans have harvested resources at this site for thousands of years, yet birds, fish and many other salt-marsh dwellers still flourish on the island (MDNR 2017). What is of most interest here is that we collected 2705 specimens from this park, more than twice that of MSP, which had the second highest abundance. Onthophagus hecate accounted for 69% of the individuals collected in this forest. This beetle is a generalist species that feeds on a wide variety of food resources, and is broadly distributed throughout the US (Price et al. 2012, Ratcliffe and Paulsen 2008, Staines 1984). In general, we believe this species is usually abundant in the Northeast where few other species are able to compete (Price 2004, Rentz and Price 2016, the present study). Competition from the wide diversity of other species found at MSP might explain why only 9 specimens were collected in MSP. Furthermore, JISP is the only site that was regularly inundated with brackish water. Salinity tolerance may be a factor inhibiting colonization by other species. Onthophagus hecate in particular has been shown to have a high tolerance for hypoxic conditions Table 4. Seasonality of dung beetles collected from 7 forests, from May 2014 to April 2015, along Maryland’s Atlantic Coastal Plain. Month Family/species Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Scarabaeidae (Aphidiinae) - - - - - - - - - - - - Alloblackburneus rubeolus - - - - 1 - - - - - - - Blackburneus stercorsus - - - - 4 - 6 6 15 - - - Irrasinus stupidus - - 11 3 - - - - - 19 4 5 Oscarinus rusicola - - - - - - 83 1 2 3 - - Pseudagolius bicolor - - - - - - - - 2 109 1 2 Scarabaeidae (Scarabaeinae) Ateuchus histeroides - - - - - 1 1 - - - - - Canthon chalcites - - - - 48 85 42 74 19 3 - - Canthon viridis - - - 1 - 5 9 5 6 - - - Copris fricator - - - - - - - - 1 - - - Copris minutus - - 16 38 8 1 13 105 164 201 237 33 Onthophagus concinnus - - - 1 33 - 4 3 7 - - - O. hecate - - - 1 392 259 428 690 162 34 - - O. orpheus - - - - 7 21 8 5 8 1 - - O. pennsylvanicus - - - - 29 165 125 60 2 - - - O. striatulus - - - - - 44 2 20 4 - - - O. subaeneus - - - - 1 - - - 1 - - - O. taurus - - - - 1 2 3 3 1 - - - O. tuberculifrons - - 6 2 114 12 6 1 72 30 - - Phanaeus vindex - - - - - 10 1 19 21 - - - Geotrupidae Geotrupes blackburnii 20 - 242 319 136 3 - - 27 865 255 181 Geotrupes egeriei - - 1 - 4 1 80 22 60 13 - - Geotrupes splendidus - - - 1 5 1 8 5 - - - - Northeastern Naturalist 96 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 Vol. 25, No. 1 (Whipple 2011), suggesting it may have a competitive advantage in low-lying, regularly flooded areas like this site. Species of concern We collected Ateuchus histeroides in SNRMA (1 specimen) and MSP (1 specimen from the diversity study and 3 specimens during the succession study). This species had been previously taken from a variety of food resources, including mammal dung, (Fincher et al. 1970, Nealis 1977, Ratcliffe and Paulsen 2008, Woodruff, 1973), from a Marmota monax L. (Woodchuck) burrow (Woodruff 1973), both vertebrate and invertebrate carrion (Payne and King 1969, Reed 1958, Walker 1957, Table 5. Heterotrophic succession of dung beetles collected in human-dung–baited pitfall traps in Martinak State Park. Beetles were collected on days 1, 3, 5, 7, 14, and 21 without replacement of dung. Species Day 1 Day 3 Day 5 Day 7 Day 14 Day 21 Total Ataenius sp. - - - - 2 - 2 Ateuchus histeroides - 1 - - 2 - 3 Blackburneus sp. - - 1 - - - 1 Canthon chalcites 2 - 1 - 1 - 4 Copris minutus 3 11 2 2 10 2 30 Geotrupes blackburnii 24 49 24 12 3 - 112 Geotrupes egeriei 27 101 10 - 2 - 140 Geotrupes splendidus - 1 - - - - 1 Onthophagus concinnus 14 8 - 2 - - 24 O. hecate 8 5 2 2 3 1 21 O. orpheus 4 - 1 - 3 2 10 O. pennsylvanicus 34 21 11 1 5 1 73 O. striatulus 2 3 6 5 9 4 29 O. subaeneus 1 - - - - - 1 O. taurus 1 1 - - - - 2 O. tuberculifrons 11 14 5 5 2 10 47 Oscarinus rusicola 2 4 5 2 1 - 14 Phanaeus vindex 1 - 1 - - - 2 Total abundance 134 219 69 31 43 20 516 Table 6. Heterotrophic succession of dung beetles collected in human-dung–baited pitfall traps in Janes Island State Park. Beetles were collected on days 1, 3, 5, 7, 14, and 21 without replacement of dung. Species Day 1 Day 3 Day 5 Day 7 Day 14 Day 21 Total Blackburneus stercorsus - - 2 1 - - 3 Canthon chalcites 126 64 43 17 44 9 303 Copris minutus 1 8 4 2 21 4 40 Geotrupes blackburnii 42 50 34 16 3 - 145 Onthophagus hecate 751 397 229 148 420 267 2212 O. pennsylvanicus 119 51 27 1 24 4 226 O. striatulus 5 11 14 23 32 17 102 Oscarinus rusicola 12 10 24 24 105 42 217 Phanaeus vindex 2 6 3 1 - 1 13 Total abundance 1058 597 380 233 649 344 3261 Northeastern Naturalist Vol. 25, No. 1 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 97 Woodruff 1973, Young 1984), rotting fungi (Woodruff 1973), and cantaloupebaited pitfall traps (Walker 1957). Young (2007) demonstrated that this species can survive and reproduce on a variety of resources. Our data confirms that A. histeroides is rare in this region. We collected Canthon viridis in TSP and SDF. This species appears to replace C. chalcites in the middle shore. Canthon viridis has been reported from mammal and bird dung, fungi, and carrion (Blume 1981, Staines 1984), and prefers dense wooded areas (Staines 1984). Copris fricator was previously reported from counties west of the Chesapeake Bay. Here we collected just 1 specimen in SNRMA, our northernmost forest. We documented Geotrupes splendidus at SDF during the diversity study, and collected 1 individual from MSP during the succession study. SDF is part of the Chesapeake Forest Lands, which has a sustainable management plan intended to be a national model for sustainable forestry and ecosystem management on public lands (MDNR 2015). Geotrupes splendidus is reportedly attracted to a variety of food resources, including fungi, mammal dung, dead animals, and chicken feathers (Fincher et al. 1970, Howden 1955). Howden (1955) suggested fungi as the preferred food. Our study found Onthophagus concinnus only in MSP and SCE, although a specimen was collected previously in TSP (D.L. Price, unpubl. data). Interestingly, this species occurs from New Jersey to Florida, but it is never common (Howden and Cartwright 1963). These authors suggest a possible explanation may be that O. concinnus is usually taken from the dung of small mammals, such as Mephitis mephitis (Schreber) (Skunk), Vulpes spp. and Urocyon spp. (foxes), (foxes), all dung sources that are not often used for sampling. Price et al. (2012) collected several individuals of this species in the Pocomoke State Forest of Southern Maryland, suggesting that it prefers sandy soils. We collected Onthophagus orpheus in all but 2 of the 7 forests we studied (JISP and HSR). This species prefers old-growth forests (Price 2004), and thus, was found here in low numbers. Onthophagus subaeneus was previously only reported west of the Chesapeake Bay. We collected just 2 specimens, one from TSP and the other MSP. This species has been taken from a variety of food resources, including fungi, dung, and carrion, and prefers moist woodlands (Staines 1984). In general, O. subaeneus is rarely in collections (Harpootlian 2001, Woodruff 1973). Conclusions Maryland’s geographic diversity spans from mountains and valleys, to rolling hills, and coastal flatlands and beaches. Wildlife distribution and abundance in this Mid-Atlantic state is dependent upon and intricately connected to the ecological integrity and diversity of its habitats (MSWAP 2015). Thus, an understanding of why certain species occur along the Coastal Plain ecoregion leads to understanding threats and allows for development of conservation actions (MSWAP 2015). While many invertebrate species are reportedly important players in the ecosystem, dung beetles are well known for their ecosystem functions and services Northeastern Naturalist 98 P. Simons, M.Molina, M.A. Hagadorn, and D.L. Price 2018 Vol. 25, No. 1 they provide (Nichols et al. 2008). Here we provide documentation of rarity for several uncommon and/or rare dung beetle species that we think merit conservation. Our findings suggested that several species are generalists either in their food or habitat preferences, but that others prefer unknown resources and deserve further investigation. Acknowledgments We thank Stephen Kelly and David Ortiz for completing a pilot study prior to this research. We are grateful to the numerous park and forest managers for their permission to collect dung beetles in Maryland, including Ryan Haley (Maryland Department of Natural Resources), Dennis Smith (JISP), Roman Jesien (Maryland Coastal Bays Program), and John Ohler (MSP, TSP, and SNRMA). We appreciate Paul Skelley (Florida Department of Agriculture and Consumer Services) for providing a reference collection for the identification of Aphodiinae specimens. 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