Ohlone Tiger Beetle
by Lukas Wegmuller
With the brilliant sun dimmed by the faint morning mist, you continue along the muddy path. The crisp air fills your lungs and the unseen birds of the forest sing a song of commencement. The surrounding redwoods twist into outreaching hands, framing the trail with a friendly vignette of branches and leaves. It is a cool spring day in Santa Cruz, California, and the forest couldn’t be more alive. A luminous green dot catches your eye in a clearing of grass, and curiosity guides you closer. Your eyes tighten with wonder -- could it be a gem? Suddenly the flickering light scurries away. You come across scattered holes the width of a pencil eraser parallel to the trail and beside them, more dazzling green colors. An adult Ohlone tiger beetle exits one of the burrows in the ground, opening its eyes to the changing world.
Unfortunately, not everyone may share this same experience, for the Ohlone tiger beetle (Cicindela ohlone) is endangered and four of its remaining five known populations are threatened (5). As described in the official U.S. Fish and Wildlife Service 5-Year Review, the “adult Ohlone tiger beetles are medium-sized, elongate beetles characterized by their brilliant metallic green coloration highlighted by stripes and spots,” (2). They are members of “the Coleopteran family Cicindelidae (tiger beetles),” (recovery plan). The beetle is endemic to Santa Cruz, California and lives in open grassland habitats with “shallow, pale, poorly drained clay or sandy clay soil that bakes to a hard crust by summer,” (2).
The beetle is predatory, both as a larva and an adult, preying on small insects. Female tiger beetles lay their eggs in the ground, and are very sensitive to soil type and moisture. Once the larva is hatched, it creates a small burrow from which it will hunt, pupate, and emerge as an adult ready to reproduce (2). The burrows are found along side trails and are threatened by foot and bike traffic, potentially collapsing the small cave and killing the larvae. The Ohlone tiger beetle typically lives two years, if not disturbed by natural or posed threats. The most significant predator to the Ohlone tiger beetle are “parasitoid wasp and flies that lay their eggs in the beetle larvae. The larvae are then consumed by the wasp or fly larvae, which then emerge from the burrow as adults,” (1). Parasitism is increasingly harmful as the Ohlone tiger beetle population dwindles. The beetle has only been found in five nearby geographic areas within Santa Cruz County, three of which are in a three mile radius of each other (4).
Despite the beetles listing in 2001 under the Endangered Species Act, the beetle experienced significant population decline from 372 adult beetles in 2003 to 116 adults in 2008. The larval burrows, however, have risen from 556 documented burrows to 583 in the same time span (2). Two petitions were sent prior to the official listing in 2001, once in 1993 and again in 1997, requesting the U.S. Fish and Wildlife Service “emergency list” the Ohlone tiger beetle as endangered (5). Based on the recovery priority system (ranking 1-18), the Ohlone tiger beetle is a 2, meaning “the taxon is a species that faces a high degree of threat and has a high potential for recovery” (2). Precise information regarding population and geographic ranges is minimal due to the fairly recent documented discovery of the beetle in 1987. Despite this high ranking, the U.S. Fish and Wildlife Service has yet to develop a recovery plan specific to the beetle, instead the beetle is included in the 1998 Recovery Plan for Insect and Plant Taxa from the Santa Cruz Mountains in California (2).
The recovery plan is intended to protect and delist endangered species within the same area as one of the five Ohlone tiger beetle populations. The plan states that urban development, agricultural conversion, recreational use, competition with nonnative plants, and overcollection of pesticides all pose threats to the Ohlone tiger beetle. The beetle inhabits coastal terraces often sought after for residential development. To ensure the survival and future protection of the Ohlone tiger beetle, we must secure and protect existing grasslands, develop habitat conservation plans for various local territories, regulate impact of nonnative plants, and conduct habitat and population research to better understand the beetle. Once we have a clear outline and have reduced harm caused by hikers, bikers, and natural erosion, we can begin locating additional habitats that fit the needs of the Ohlone tiger beetle. (3)
As a Santa Cruz local myself, it is hard to see a creature suffer from the neglect and destruction of us humans. Some of the remaining populations live by the same trails I’ve walked my entire life and I’m surprised to have only heard about their endangerment this year. To do your part in protecting the Ohlone tiger beetle and other endangered species, write to your city council and express the importance of proper management. Tell them that you care about your local wildlife and that they should thoroughly think through any city planning that may affect surrounding habitats. The Ohlone tiger beetle was previously threatened by proposals of a ballfield, a school, and residential development near their few remaining habitats (5). On a more personal level, be courteous in nature! Be aware of your surroundings and know we share the same earth as thousands of other creatures. It is our duty to stand up for those without a voice.
Resources:
- "Ohlone Tiger Beetle." Wikipedia. Wikimedia Foundation, n.d. Web. 29 Nov. 2016.
- U.S. Fish and Wildlife Service. Ohlone Tiger Beetle (Cicindela Ohlone) 5-Year Review: Summary and Evaluation. Ventura, California, 2009. Print.
- U.S. Fish and Wildlife Service. Recovery Plan for Insects and Plant Taxa from the Santa Cruz Mountains in California. Portland, Oregon: 1998. Print.
- Morgan, Randall. "RE: Ohlone Tiger Beetle." Letter to U.S.F.W.S. Regional Office. 12 Feb. 1993. MS. Portland, Oregon.
- Grey. "Petition: Ohlone Tiger Beetle." Letter to U.S. Fish and Wildlife Service. 25 Apr. 1997. MS. Ventura, California.
Tiger beetle photo courtesy of Maycee Hash
Most people wouldn't see the need to save an insect species. It raises an interesting point on human's priorities. It's much more glamorous to champion the preservation of keystone species, but insects are just as important.
ReplyDelete-Emily Sydow
I usually do not pay attention to beetles, but your introduction paragraph got me intrigued to read the rest of the blog. I think that even if a species is tiny and might not affect us directly, it is still important to learn about them. I will be more aware of my surroundings especially when I am in Santa Cruz!
ReplyDelete-A. Walle
I really appreciated your intro paragraph, as you were able to effectively draw me in and bring my attention to a species that I probably would not have noticed or given any thought to otherwise. Despite the fact that a species as small as beetles may not be as apparent to humans, it does not mean that their problems and threats are any less significant than those of other species.
ReplyDelete- Nicholas Tyra