Tanner's Black Camel Cricket
Utabaenetes tanneri
Other common names: Sand Treader
NatureServe conservation status
Global (G-rank): G1G3
State (S-rank): S2
Utah Wildlife Action Plan status
- SGCN
External links
General information
The Tanner’s black camel cricket/sand treader, Utabaenetes tanneri, is a large black cricket in the family Rhapidophoridae. All crickets in this family lack specialized morphology found in other crickets to create ‘songs.’ The sand treader does not have a wide geographical range, but can be found in large concentrations within this range. Adults are active between April and June, with a few observed in July (Shofner, 2014). These crickets are omnivores, preying on fungus, fecal pellets, insects, and plants (Graham, 2017). The sand treader falls prey to many predators including lizards, scorpions, beetles, coyotes, and birds (Shofner, 2014).
Species range
This sand treader may be endemic to the Colorado Plateau, with observations in southern Utah located in the San Rafael Swell, Emery county, Garfield county, and Wayne county.
Ecology
Some specimens vary in color from tan to black; it is not known whether the nymphs are pale tan in coloration, becoming black after maturation and exposure to increasing heat as the temperature increases in the spring. Found with other Orthopteran species: Trimerotropis agrestis gracewileyae, T. salina, Plagiostira gilletti, and an undescribed species of Ammobaenetes (Tinkham 1970).
Reproductive characteristics
The sand treader nymphs have tan colorations and are primarily nocturnal (Graham, 2017). Adults are shiny and black, with females easy to differentiate from males by the presence of an ovipositor extending from their abdomen. As part of courtship behavior, males create curved lines in the sand by wagging a pheromone-producing gland on their abdomen and motioning back and forth as they walk. This pheromone trail is thought to attract any nearby females and potentially define territory. Males fight each other for burrow space and females by backing up and kicking sand towards their opponent. Females are not interested in other crickets, unless a male approaches her for mating (Shofner, 2014). To mate, a male will back his abdomen up to a female, which may or may not reciprocate. If she does accept, she will respond by backing her abdomen to the male, who passes his spermatophore to her, and the copulation process lasts approximately a minute (Graham, 2017). This species has been observed mating from midnight to dawn.
Threats or limiting factors
Aside from being a prey species to a large number of local predators, the biggest threat to the sand treader is its range constraint and population isolation. Any environmental shifts in the sand dunes of the Colorado Plateau region would severely impact this cricket. The second greatest threat to the sand treader is widespread drought affecting the western United States. Dust generation during drought has been found to cover snowpacks of nearby mountains, causing rapid snow melt and loss of input to the water sources of the region (Nauman et al., 2018). Lower rainfall and snowmelt levels decrease sand cohesion needed for cricket burrow construction and success (Shofner, 2014).
Direct human impacts to the sand treader include dispersed camping, off-highway vehicle (OHV) recreation, and dirt roads. Dispersed camping throughout the Colorado Plateau has been shown to spread the expanse of the human footprint on vulnerable basin regions (Monz, 2021). OHV recreation disturbs soils through mechanical means and plant ecology alterations (nonnative introductions and destruction of natives). During drought conditions, these disturbances have an even greater impact by creating soil structure instability and possible sand dune migration shifts (Nauman et al., 2018). OHV trails cut through a large portion of the known sand treader population locations, possibly leading to burrow construction failure by soil degradation and eventual wind erosion. Dirt roads have not been proven to be a large threat, but they do create habitat fragmentation (Monz, 2021).