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Cicindela tranquebarica joaquinensis site in the San Joaquin Valley of California after heavy grazing and drought severely reduced vegetation.
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This review summarizes the literature and some primary data on the effects of anthropogenic disturbances on tiger beetle habitats, including how this may help or harm populations of rare species, and how understanding these effects is important in tiger beetle conservation and management. The main focus is on U.S. species but relevant literature fr...
Contexts in source publication
Context 1
... species of western tiger beetles, including C. obsoleta Say, C. purpurea Olivier, C. hornii Schaupp, and C. debilis Bates, are found primarily in grasslands and mountain meadows where grazing by livestock and digging by rodents create open patches upon which these species depend. Cicindela tranquebarica joaquinesis Knisley and Haines, a tiger beetle restricted to only a few sites in the San Joaquin Valley of California, declined at two sites that were nearly denuded of vegetation by a combination of heavy cattle grazing and extended drought (Knisley and Haines, 2010 ) ( Figure 5 ). At two other sites where grazing was more limited, cattle improved conditions for the beetle by reducing vegetation density and height. ...
Context 2
... attributed to OHV use (Shook and Clark, 1988 ). e most obvious e ff ect of vehicle activity is direct killing or injury to adult beetles by being run over. At the Coral Pink Sand Dunes in Utah, adults of C. albissima Rumpp ( Figure 1G ) have been found dead or badly injured from OHV runovers, especially during holiday weekends (Knisley and Hill, 2001 ). Experimental trials with an OHV found adults were more likely to be injured or killed on wet or compact sub- strates than on soft sand (Knisley and Hill, 2001 ). Mountain bikes have been found to kill or injure adults of C. ohlone along trails in several Santa Cruz, California sites (USFWS, 2009). A less dramatic but probably more signifi cant impact of pedestrian foot tra ffi c and even limited vehicle activity than direct mortality is the disruption of feeding of both adults and larvae and mating and oviposition of adults. ese disturbances may also cause adults to disperse to less disturbed areas. e decline of Lophyridia concolor (Dejean) from heavily used tourist beach areas in Turkey was attributed to e ff ects of trampling on larval feeding and normal development (Arndt et al., 2005 ). Larvae are unlikely to experience direct mortality from runovers because they can retreat down into their burrows. In a test of military training impact at Dugway Proving Ground larvae of C. decemnotata reopened their burrows within a few days of being run over by a Paladin tank which compacted the soil several centimeters (Knisley, 2010 ). However, repeated disturbance of the soil surface by vehicles or trampling can signifi cantly impact larval activity and development. Stamatov ( 1972 ) suggested the decline of C. d. dorsalis in the Northeast was probably due to disturbance of the soil surface in the upper tidal beach zone where larvae occurred. In a study with this species at a Maryland beach site, numbers of early fi rst instar larvae were comparable in plots fenced to prevent foot tra ffi c and unfenced plots exposed to pedestrian beach use, but after several weeks, larval survival was signifi cantly greater in fenced plots where soil surface was undis- turbed (Knisley and Schultz, 1997 ). e way that vehicles and pedestrian foot tra ffi c a ff ect larval activity and develop- ment has been suggested in several studies. Schultz ( 1988 ) suggested the disappearance of C. oregona maricopa Leng from Arizona river edge sites was due to disruption of the soil particle size and moisture gradients by OHVs. A similar e ff ect was documented at Coral Pink Sand Dunes on OHV trails where the cutting and mixing of the soil surface resulted in reduced soil moisture and probably explained why there were fewer C. albissima larvae than in adjacent areas that were protected from vehicles (Knisley and Gowan, 2008 ). Cornelisse and Hafernik ( 2009 ) found that increased soil compac- tion from experimental trampling at a northern California beach signifi cantly reduced larval numbers of both C. oregona LeConte and C. hirticollis Say. ese workers sug- gested compaction from trampling reduced the soil pore space and moisture of the sandy soils. e impact of soil compaction on oviposition and larval survival is prob- ably greater in clay or silty soils as indicated above for C. decemnotata and C. ohlone . High and persistent livestock grazing can negatively impact tiger beetle populations, but may also improve tiger beetle habitats by reducing the density and height of vege- tation and creating trails and open patches. e activities of smaller animals like gophers and ground squirrels produce piles of fresh soil and create bare patches in grasslands and meadows. Studies with C. ohlone indicated that adults and larvae at several sites were largely restricted to cattle trails because the interior habitat was too densely vegetated (Knisley and Arnold, 2004 ). At one of these sites the population was lost three years after grazing was terminated because rapid encroachment of herba- ceous vegetation eliminated open ground ( Figure 4 ). Although some larvae were lost by cattle hooves cutting into larval burrows, this loss was more than o ff set by improved habitat which sustained the population. At several other sites the bare patches created by rooting of feral hogs and digging by ground squirrels and pocket gophers was used by C. ohlone adults for foraging, thermoregulation, and oviposition (Knisley and Arnold, 2004 ). Several species of western tiger beetles, including C. obsoleta Say, C. purpurea Olivier, C. hornii Schaupp, and C. debilis Bates, are found primarily in grasslands and mountain meadows where grazing by livestock and digging by rodents create open patches upon which these species depend. Cicindela tranquebarica joaquinesis Knisley and Haines, a tiger beetle restricted to only a few sites in the San Joaquin Valley of California, declined at two sites that were nearly denuded of vegetation by a combination of heavy cattle grazing and extended drought (Knisley and Haines, 2010 ) ( Figure 5 ). At two other sites where grazing was more limited, cattle improved conditions for the beetle by reducing vegetation density and height. Bauer ( 1991 ) found cattle grazing reduced vegetation encroachment in Idaho sand dunes habitat of C. arenicola, although their trampling signifi cantly reduced numbers of active tiger beetle larvae. Cattle trampling was responsible for the decline and near extirpation of the rare blue endemic form of C. circumpicta johnsonii Fitch ( Figure 1H ) at the Missouri site that once supported the largest population (Brown and MacRae, 2003 ). e endangered Salt Creek Tiger Beetle, C. n. lincolniana Casey, has also been negatively impacted by cattle grazing (USFWS, 2005). Removal and/or relocation of soil at sand and gravel pits and the placement of spoil deposits from channel dredging onto shorelines create open areas of bare soil that may be readily colonized by tiger beetles ( Table 1 ). Kritsky et al. ( 1999 ) found fi ve tiger beetle species colonized sand piles in Ohio within one year, peaking to nine species at 30 years, before declining to four species after 55 years. Mawdsley ( 2007b ) found seven species of Cicindela in an anthropogenic sand barrens site in Maryland. A study of the e ff ect of dredge sand placement on Cicindela d. dorsalis habitat at two sites along the Chesapeake Bay in Virginia found that adults quickly moved to newly deposited beaches and recruited large numbers of larvae within several months of the place- ment (Fenster et al., 2006 ). ese results are consistent with fi eld surveys that show C . d. dorsalis prefers dynamic beach areas where new sand has been deposited from accretion or washovers (Knisley et al., 1998 ). A large population of C. hirticollis and smaller numbers of four other species colonized newly deposited sand along a beach in the Upper Chesapeake Bay (Staines, 2005 ). Wilson ( 1970 ) found C . duodecemguttata Dejean adults colonized new sand piles within a few days of being deposited and pro- duced larvae the following year. e e ff ects irrigation and cultivation on tiger beetles have not been well studied, but the literature suggests these activities may create habitat or in other cases be detrimen- tal. Some common tiger beetle species have been reported from agricultural crops and orchards where they may feed on pest insects (Knisley and Schultz, 1997 ; Young, 2005 ; Nachappa et al., 2006 ; Sinu et al., 2006), but some rare species may also depend on agricultural habitats. Recently, populations of C. tranquebarica Herbst, including the only known remaining population of C. t. viridissima Fall, have been found in irrigated California fruit orchards (Knisley, unpublished notes). e presence of adequate mois- ture from irrigation and the soft sandy soil in these orchards apparently provide favo- rable conditions because the populations at these sites were large and have persisted for 10+ years. Another rare California species using irrigated agricultural sites is Cicindela lunalonga Schaupp. is species was known from only one population in Lassen County and believed extirpated from all historic sites in the San Joaquin Valley (Woodcock et al., 2006 ) until rediscovered in 2009 along irrigation ditches in an intensely cultivated and irrigated area of the San Joaquin Valley (Knisley and Kippenhan, 2010) ( Figure 6 ). is fi nding suggests C. lunalonga has successfully transitioned from its historic wetland habitats and readily adapted to the abundant moisture available in this highly disturbed agricultural region. Areas of intense irrigation may damage tiger beetles habitats by lowering of the water table and desiccating surface and near surface soil moisture needed by larvae. Tiger beetles believed to have declined as a result of this impact are the very rare C. t. joaquinensis in the San Joaquin Valley (Knisley and Haines, 2007 ), C. praetextata LeConte along the lower Colorado and Virgin Rivers (Knisley, unpublished studies), C. oregona maricopa in Arizona (D. L. Pearson, pers. comm.), and C. willistoni sulfontis Rumpp and C. nevadica citata Rumpp in the Sulphur Springs Valley, Arizona (Pearson et al., 2006 ). e decline and endangerment of C. deserticoloides in Spain was attrib- uted to the conversion of its salt steppe habitat to agricultural lands by drainage and desalination (Diogo et al., 1999 ). Many of the 30+ species and 50+ subspecies of U. S. tiger beetle species found along rivers or coastal areas in the U. S. are potentially impacted by dams, water diversions, and shoreline structures. ese dynamic habitats experience regular natural distur- bances from water level changes that can result in deposition of point bars and new soil upon which many tiger beetles depend. Additions of dams or water diversions can signifi cantly impact these point bar habitats. For example, impacts from the Shasta and Oroville Dams on the Sacramento and Feather Rivers in California caused the decline and ultimately the apparent ...
Citations
... The effects produced by the presence and locomotion of large mammals on open ground can have a positive impact (commensalism) on smaller fauna. For instance, grazing and trampling cattle remove vegetation and maintain open habitats which benefit and sustain tiger beetle populations, even considering losses that result from cattle hooves cutting into their larval burrows (Knisley 2011). Wallowing or trampling by ungulates such as bovids and wild boar can create pools of water that are needed by amphibians or aquatic insects (Williams 1997;Baruzzi and Krofel 2017). ...
Biotic interactions (e.g., predation, competition, commensalism) where organisms directly or indirectly influenced one another are of great interest to those studying the history of life but have been difficult to ascertain from fossils. Considering the usual caveats about the temporal resolution of paleontological data, traces and trace fossils in the sedimentary record can record co-occurrences of organisms or their behaviours with relatively high spatial fidelity in a location. Neoichnological studies and studies on recently buried traces, where direct trophic links or other connections between tracemakers are well-known, may help interpret when and where overlapping traces represented true biotic interactions. Examples from Holocene paleosols and other buried continental sediments in Poland include the tight association between mole and earthworm burrows, forming an ichnofabric representing a predator–prey relationship, and that of intersecting insect and root traces demonstrating the impact of trees as both ecosystem engineers and the basis for food chains. Trampling by ungulates, which leaves hoofprints and other sedimentary disturbances, may result in amensal or commensal effects on some biota in the short term and create heterogeneity that later trace-making organisms, such as invertebrate burrowers, can also respond to in turn, though such modified or composite traces may be challenging to interpret.
... A nivel mundial, la región Neártica ocupa el quinto lugar en cuanto a riqueza de géneros y especies de escarabajos tigre (Gough et al., 2018). En México, el género con mayor número de especies y registros es Cicindelidia -anteriormente conocido como Cicindela-, que habita comúnmente en zonas arenosas, desérticas y en pastizales con poblaciones muy abundantes y se distribuye en gran parte del territorio nacional (Cazier, 1954;Knisley, 2011;Pearson y Vogler, 2001;Rodríguez et al., 1994). Por otra parte, el resto de los géneros (Amblycheila Say 1830, Cicindela Linne 1758, Cylindera Westwood 1831, Dromochorus Guerin-Meneville 1845, Ellipsoptera Dokhtouroff 1883, Eunota Rivalier 1954, Habroscelimorpha Dokhtouroff 1883, Microthylax Rivalier 1954y Opilidia Rivalier, 1954 que se distribuyen ampliamente en toda la región Neártica son géneros que tienen un bajo número de especies y distribución restringida en México (Duran y Gough, 2019; Pearson et al., 2015). ...
Resumen Se describen la riqueza y diversidad beta de escarabajos tigre (Carabidae: Cicindelinae) en las 3 regiones y 14 provincias biogeográficas de México. Con información de bases de datos, colecciones entomológicas y literatura publicada se recabaron 6,501 registros pertenecientes a 4 tribus, 16 géneros y 122 especies de cicindelinos distribuidas en México. A nivel nacional, el estimador Chao1 predijo 128 especies, por lo que el inventario estaría completo en 95%. Las provincias con la mayor riqueza fueron el Desierto Chihuahuense, Tierras Bajas del Pacífico y Veracruzana, mientras que la menor riqueza se registró en las provincias Californiana, Tamaulipas y Península de Yucatán. Se estimó la diversidad beta y sus componentes de recambio y anidamiento entre regiones y entre provincias biogeográficas. La mayor diversidad beta se presentó entre las provincias de la Zona de Transición Mexicana. En la mayoría de los casos, el recambio fue el principal componente de la diversidad beta. Este trabajo describe la distribución de las especies de cicindelinos en las provincias biogeográficas del país, pero a escala local aún son necesarios estudios para entender la ecología de estos insectos, los factores que determinan sus patrones de distribución y sus respuestas a los cambios ambientales.
... Nonetheless, the results also pointed to at least one species of Enchytraeidae, Achaeta eiseni, being favoured by paths and two others were found exclusively in the soil under the paths (Pižl and Schlaghamerský, 2007). Knisley (2011) reviewed the anthropogenic impacts on tiger beetles (Cicindelinae), among which studies on the effects of roads and hiking trails were mentioned. Some studies showed that certain species occurred almost exclusively in highly disturbed areas, while others found that colonization by invasive grass species led to the reduction or loss of populations, though in other sites they were preserved due to paths that were maintained by bicycles, pedestrians, motor vehicles and animals. ...
... Some studies showed that certain species occurred almost exclusively in highly disturbed areas, while others found that colonization by invasive grass species led to the reduction or loss of populations, though in other sites they were preserved due to paths that were maintained by bicycles, pedestrians, motor vehicles and animals. Anyway, severe declines or even extirpation of populations of coastal tiger beetle species caused by vehicle and foot traffic were observed (Knisley, 2011). Another interesting study assessed and compared the different responses of beetle communities in Finland and Canada to trampling intensity (Kotze et al. 2012). ...
... Several studies over the years have shown this to be the case for diverse biomes, different spatial and temporal scales and for a wide range of conditions and impacts (Brooks et al. 2012, Cameron and Leather 2012, Cajaiba et al. 2018, Magura et al. 2018, Knapp et al. 2019. Within the context of road and trail impacts, several of the studies here reviewed attest to the suitability of carabids for ecological impact indication (Grandchamp et al. 2000, Koivula 2005, Koivula and Vermeulen 2005, Lehvävirta et al. 2006, Noordijk et al. 2006, Katarzyna and Jarosław, 2008, Melis et al. 2010, Yamada et al. 2010, Knisley 2011Kotze et al. 2012). As such, joining with previous researchers (Grandchamp et al. 2000, Rainio and Niemelä 2003, Lehvävirta et al. 2006, Muñoz et al. 2015, we advocate carabids as a relevant taxon with a large potential, not by simply relying on past studies to identify suitable speciesas has been done for the classification species regarding habitat preferences (Grandchamp et al. 2000, Koivula 2005, Lehvävirta et al. 2006, Kotze et al. 2012) -but rather as a strong and practical option amongst all the possible taxa that can be sampled, based on available evidence. ...
Hiking is a natural exercise that has become one the most popular outdoor activities, promoting physical fitness and de-stress without large investments or special equipment. However, hiking has downsides, particularly in the areas in which it takes place. From soil compaction and erosion to disturbance and ecological impacts, mounting evidence shows that it is far from innocuous to ecosystems. Despite spanning several decades, research on the impacts of hiking on ecosystems and particularly on the pertinence of using ecological indicators is still scarce. This work reviews the published information conducted with invertebrates and, by doing so, offers insights to guide not only management actions but also further investigation in this scope. We address some of the current knowledge gaps and provide recommendations by focusing on ground beetles (Coleoptera: Carabidae) for their sensitivity to disturbance, representativeness but also due to their taxonomic and functional diversity. Due to the limited number of studies published so far, the classification of species based on their habitat preference, within the context of trail impacts, is non-consensual. Alternatively, such classification should derive from its respective study and avoid being generalized, or done with great caution. Additionally, sampling methods that distinguish mortality from behavioural changes were considered crucial to determine possible effects. Ultimately, the joint use of both vegetation and invertebrates, particularly ground beetles, was considered relevant to assess hiking trail ecological impacts.
... Tiger beetles are one of the most studied groups of non-pest insects [1,2] and have been used as models organisms in conservation biology and biodiversity assessments [3,4]. Most of the fauna of North America had been described by the mid-1800s and by the latter half of the 1900s it appeared as if nearly all of the diversity had been discovered and named [5]. ...
Tiger beetles are a popular group of insects amongst amateur naturalists, and are well-represented in museum and private collections. New species descriptions plateaued in the 19th century, but there is a recent resurgence of discoveries as integrative taxonomy methods, guided by molecular systematics, uncover "cryptic" tiger beetle diversity. In this paper, we describe a new species using multiple data types. This new species, Eunota mecocheila Duran and Roman n. sp., is in the tribe Cicindelini, and is described from specimens collected in saline muddy ditches in northern Mexico. This species is closely related to E. circumpicta (LaFerté-Sénectère, 1841), but is separated based on morphological differences, geographic range, and genetic differentiation. Little is known about the biology or distribution of this species and it has only been collected from two sites in the state of Coahuila. Given the location of this new species, and its genetic divergence from its closest relative, E. circumpicta, we discuss the historical biogeography that may have led to isolation and speciation. The male and female dorsal, lateral and frontal habitus and the male aedeagus are shown.
... By measuring the values of given traits that are predominant in a given assemblage under given environmental conditions, one can infer which life-history strategies are selected under these conditions. For example, when sward is grazed short and bare soil is exposed, this often leads to an open habitat with warmer microclimate, which could be beneficial for the occurrence and development of various arthropods tolerant to high temperatures (Zhu et al. 2020), or taxa which need open areas to forage or deposit their eggs (Knisley 2011). Patches of tall and dense vegetation, on the other hand, may cool temperatures, and support arthropods that deposit their eggs on or inside plants (van Klink et al. 2015). ...
Livestock grazing puts major anthropogenic pressure on biological communities worldwide. Not all species are expected to be affected in the same way, and the impacts will depend on species’ traits. Focusing on traits thus helps identify the mechanisms underlying changes in community composition under grazing pressures. We investigated how fine-scale grazing heterogeneity affects the trait composition and diversity of dung beetle assemblages in Western Europe. We sampled dung beetles in habitat patches differing in terms of grazing intensity within rangelands of two distinct biogeographical areas: a Mediterranean lowland steppe and Western alpine meadows. We measured five morphological traits expected to respond to the local-scale filtering pressure exerted by variations in grazing intensity. Using individual-based data, we assessed responses in terms of single-trait mean values in communities and complementary trait diversity indices. We found strong shifts in trait composition and diversity between the habitat patches. In both study areas, variations in habitat conditions are likely to have filtered the local occurrence and abundance of dung beetles by the mean of traits such as body mass (which have several functional implications), as well as traits linked to underground activity. We hypothesize that fine-scale variation in resource availability (i.e., droppings) and disturbance intensity (i.e., trampling) are key drivers of the observed patterns in species assemblages. Trait richness peaks at moderate grazing intensity in both study areas, suggesting that patches with an intermediated level of available resources and soil disturbance enable individuals with a greater range of autecological requirements to coexist.
... Tiger beetles are among the most well-studied groups of invertebrates (Knisley and Schultz 1997;Pearson and Vogler 2001) with their conservation biology as a key focus area (Schultz 1988;Pearson and Cassola 1992;Knisley and Hill 1997;Bouffard et al. 2009;Cornelisse et al. 2013;Knisley et al. 2014). Due to their ecological niche specificity and sensitivity to environmental degradation, tiger beetles have been proposed as bioindicators of habitat quality (Knisley and Schultz 1997;Knisley 2011). In the United States, numerous species and subspecies (15% of the total taxa) are reported to be declining or sufficiently rare to be considered for listing by USFWS (Pearson et al. 2015). ...
... Several taxa are currently listed as threatened or endangered at the international (Vié et al. 2009) and federal (Knisley et al. 2014) levels, and still others are protected at the state level. A primary cause of tiger beetle declines is habitat destruction/fragmentation (Knisley et al. 2014) but habitat succession and the lack of natural disturbance processes is also an important threat to the many tiger beetle species that are dependent on open, early-successional habitats (Knisley 2011;Knisley and Gwiazdowski 2020). ...
... Natural disturbance processes at inland sites may be rare, apparently due to widespread fire suppression in the region (Luque 2000), and habitat must either be maintained through active management (e.g. controlled burns) or be incidentally created and maintained as a result of sand mining, road maintenance, and forest management (Knisley 2011). Whether intentional or incidental, moderate to intense disturbance in the Coastal Plain of New Jersey often results in wide areas of loose, white "sugar sand" that is sparsely vegetated or bare. ...
Background
Ellipsoptera lepida, the ghost tiger beetle, is in decline throughout much of its range, especially in the northeastern United States. In New Jersey, the species was known from 18 historic coastal dune and interior upland sites, although modern collection records for the species are rare.Aims/Methods
Because of the decline of E. lepida, the authors performed extensive surveys of historic sites, as well as potential undocumented sites based on satellite imagery during 2014–2015. One of the previously undocumented sites was an anthropogenic dune on a developed barrier island that had only been constructed 3–4 years prior. Because of its novelty, we conducted more intensive surveys at this site to document abundance and characterize adult and larval habitat.ResultsMany historic sites were apparently extirpated or contained small numbers of beetles, although several new populations were located at coastal and inland sites. Abundance of adults and larvae in constructed dunes greatly exceeded densities recorded at other coastal sites. An analysis of vegetation density based on satellite imagery indicates that E. lepida larvae and adults depend on early and mid-successional dunes for optimal habitat.DiscussionNearly all inland sites appear to be suitable only because of incidental anthropogenic habitat disturbance while natural disturbance processes play a greater role in maintaining habitat at coastal sites. The high densities we observed in constructed dunes are likely because the constructed dune system is at a single, highly suitable successional stage. This species is unlike another rare coastal tiger beetle native to New Jersey, Habroscelimorpha dorsalis, in that it can persist in the presence of beach vehicle and pedestrian disturbance if suitable dunes are available.Implications for insect conservationOur findings indicate the potential for creating and maintaining additional habitat for Ellipsoptera lepida in parts of its range where it may be declining.
... Each species rarely occurs in more than one or a very few habitat types and habitat associations tend to be highly specific (Morgan et al., 2000;Rafi et al., 2010;Borges et al. 2007;Scudder et al. 2005). (Wiesner, 1975;Satoh et al., 2003;Knisley and Fenster, 2005;Knisley, 2011;Arnett, 1973;Chandra 2007;Chandra and Ahirwar, 2005) Fig. 1. Total 15 sampling spots were selected from the Akola district. ...
A survey was organised from August 2016 to February 2020 in the forest areas and agricultural areas of Akola district to know the diversity of Beetles for further research. A total of 68 genera and 90 species belonging to 13 different families of beetles viz. Buprestidae (Metallic Wood-boring Beetle), Carabidae (Ground Beetles), Cerambycidae, Chrysomelidae (Leaf beetles), Coccinellidae, Dytiscidae, Geotrupidae, Gyrinidae, Hydrophilidae, Hybosoridae, Meloidae (Blister Beetles), Scarabaeidae, Tenebrionidae (Darkling Beetles) were collected and identified from various habitats along with their valid scientific names, systematic position, and distribution within agricultural fields and forest areas of Akola district.
... Significant contributions to the biology and taxonomy of this group are due to the efforts of amateurs, alone or in collaboration with professional entomologists (Pearson 2013, Russell 2014, Pearson et al. 2015, which support or become the academic basis for much of what we know about their biology, systematics, and conservation genetics. Because tiger beetles are often the best-known organisms in their habitats, they have been used as indicators to assess habitat quality and disturbance/impacts , Knisley 2011) and as indicators of biodiversity in several continents (Pearson and Cassola 1992, Cassola and Pearson 2000, Pearson and Carroll 2001. This high level of interest in tiger beetles, ease of identifying the species in the field, and the available information on their distribution and biology has highlighted their value as a flagship group in insect conservation (Knisley and Schultz 1997, New 2010. ...
... The natural disturbances from wildfires, grazing, and flooding, which historically created these open spaces, have been largely eliminated, resulting in the encroachment of native and invasive vegetation. Consequently, some of these rare tiger beetles depend on human-related disturbances to create and maintain open habitat areas (Knisley 2011). In addition, disturbance strategies have been implemented as key conservation strategies for some of these listed species, as detailed below. ...
Tiger beetles are a popular, widely studied group of charismatic insects that are a flagship taxon for insect conservation. Five species are currently listed in the United States as Federally Endangered or Threatened, two others have recently been delisted, and many more are listed by individual states. To date, the status of some of these species has been improved or their decline slowed by various conservation strategies. In this article, we review the background and the recent conservation activities for all federally listed tiger beetle species. These species have lost much of their historic habitat and remain at risk because of continuing impacts from vegetation encroachment of native or invasive plants, water-level changes, and other human-related activities. Conservation efforts are limited because for most species there is little or no potential habitat remaining, even following restoration activities. Effective strategies have included long-term monitoring of population size and research activities, acquisition and protection of occupied sites, methods for controlling vegetation encroachment to improve habitat quality, and recent efforts with translocations using beetles from existing populations or from captive rearing. Because tiger beetle life histories are similar, successful management and research methods for any one species can be applicable to others. This presents an opportunity to coordinate taxon-level conservation for all U.S. species through cataloged information and conservation leadership
... This is very important particularly in analyzing habitat change and the data will also serve as input to policy towards conservation of our species (Cassola & Pearson, 2000). Considering that the Philippines is a mega-diverse country at the same time a megadiverse hotspot (Catibog-Sinha & Heaney, 2006;Heaney & Regalado, 1998;Mittermeier et al. 2004Mittermeier et al. , 1999Myers, 1998;Myers et al. 2000) while climate change (Lasco et al. 2008) and human disturbance (Arndt et al. 2005;Costa & Zalmon, 2019;Knisley, 2010;Knisley & Brzoska, J o u r. T r o p. C o l e o p. 1 ( 2 ), 25 -34 C o p y r i g h t @ 2 0 2 0 U n i v e r s i t y P r e s s ...
... All of these mountain ecosystems have several farmlands causing the forest ecosystem to be fragmented. It has been documented in several studies on the effect of human interventions on insect fauna (Costa & Zalmon, 2019;Ganeshaiah & Belavadi, 1986;Knisley, 2010;Knisley & Hill, 1992;Myers, 1988;Myers et al. 2000). In the case of Heptodonta nigrosericea (W.Horn, 1930), the species thrive in the junction between high elevation (900-1000+ masl) open farmland and secondary and primary forests (Medina et al. 2020b). ...
This paper provides additional proof that tiger beetles have specific habitat preferences based on ten years of field observations from the five protected mountain ranges in Davao Region, Mindanao, Philippines. Species-specific occurrence is more helpful in habitat assessment than using the whole taxon. Each tiger beetle species reflects specific habitat types. Thopeutica Chaudoir, 1861 prefers healthy forest and pristine fluvial systems. Heptodonta nigrosericea (W.Horn, 1930) prefers to inhabit between close forest canopy and agro-ecosystem, while species under Calomera Motschulsky, 1862, Cylindera Westwood, 1831, and Therates Latreille, 1816 can tolerate certain degrees of human disturbance. Using tiger beetles as indicator species should require identification up to species level and the type of habitat they occupy. Furthermore, species occurrence is more dependent on ecosystem type rather than the elevation gradient.
... Because tiger beetles can be the best-known organisms in their habitats, many species are important indicators of impacts to other biodiversity [8][9][10]. Consequently, in light of ongoing habitat loss and projected climate change [11], the taxonomy and phylogeny of many ostensibly well-known North American species and species complexes are being re-examined using genetic analyses e.g. ...
The cobblestone tiger beetle, Cicindelidia marginipennis (Dejean, 1831) is a North American species specializing in riparian habitats from New Brunswick, Canada, to Alabama in the United States. In the United States, this species is state-listed as threatened or endangered range-wide and periodically receives consideration for federal listing, mostly due to habitat decline. Despite its conservation status, intraspecific genetic diversity for this species has not been explored and little is known about its natural history. To support further inquiry into the biology of C. marginipennis, this study provides the first look at range-wide genetic diversity using mitochondrial DNA (mtDNA), describes all three larval instars, and describes natural history characteristics from captive rearing and field observation. Based on mtDNA analyses, our results suggest that geographically based population structure may exist throughout the range, with individuals from Alabama possessing haplotypes not found elsewhere in our sampling. Further genetic analyses, particularly multi-locus analyses, are needed to determine whether the Alabama population represents a separate cryptic species. Our morphological analysis and descriptions of larval instars reveal a combination of characteristics that can be used to differentiate C. marginipennis from closely related and co-occurring species. Based on our field observations, we find that the larval “throw pile” of soil excavated from burrows is a key search image for locating larvae, and we provide descriptions and detailed photographs to aid surveys. Lastly, we find that this species can be successfully reared in captivity and provide guidelines to aid future recovery efforts.
