Hine's emerald

The Hine's emerald's appearance varies across its lifetime. During the larval stage, nymphs possess no features that distinguish them from those of other dragonfly species. A mature nymph measures roughly in length. == Life history ==

During their lifespans, Hine's emeralds progress through the egg stage, larval stage, and adult stage. Both the egg and larval stages are aquatic. Hine's emeralds spend the majority of this lifespan in the larval stage, which lasts 2–4 years. Nymphs typically emerge into the wild during June and July. Male and female nymphs appear to progress into the adult stage in equal proportions. The following 4-to-6-week-long adult stage consists of three sub-stages. These stages are the pre-reproductive stage, reproductive stage, and post-reproductive stage. Adults spend these stages hunting for prey, establishing territories, and reproducing. == Distribution and habitat ==

Hine's emeralds occupy wetland, pond and pool, wet meadow, forest, and marsh habitats. Fourth, typical habitats possess exposed or lightly covered bedrock. Finally, they provide pathways for Hine's emerald dispersal. Roadways, forest clearings, streams, and railroads all serve as dispersal pathways. Populations at one point also existed in Ohio, Alabama, and Indiana, though there have been no recent sightings. == Ecology ==

Several species prey upon the Hine's emeralds. Crayfish, turtles, amphibians, and other aquatic species prey upon nymphs. It is unknown whether the Hine's emeralds have similar mutually beneficial relationships with other species. == Population size ==

Not much information exists about historical population size for Hine's emerald dragonflies. The IUCN Red List states that current populations are stable, estimating that there are over 30,000 individuals globally. the Door County, Wisconsin population is the biggest and most significant, with as many as 20,000 individuals. There are two recovery units in the United States: the Northern Recovery Unit and the Southern Recovery Unit. The Northern Recovery Unit has two populations: Northern Wisconsin and Michigan. The Southern Recovery Unit has four populations. This includes Ozaukee County Wisconsin, Southwest Wisconsin, Illinois, and Missouri. Populations are unique when separated by large distances of at least 30 miles. There must be a low chance of genetic exchange between them. These six populations are made of 27 sub-populations. Thus, there are 69 total sites for Hine's emerald presence. Thirty-five of these sites are fully protected and 21 are partially protected. Eleven sites are not protected, and the remaining two have unknown statuses of legal protection. Information is missing on the number of breeding adults for many of the sub-populations. This makes it difficult to assess progress in conservation efforts. The 2013 Five Year Review suggests future actions that aid conservation efforts. This includes modeling Hine's emerald population dynamics, a high priority. Additionally, more information about key measures of population demographics is required. Areas of research include smallest possible population sizes and current population sizes. Also, the genetic diversity between populations is important to study. Restoring Hine's emeralds to lasting population sizes allows the ESA to downgrade the species from endangered to threatened. To do this, however, up-to-date population data is crucial. == Conservation ==

Conservation status Hine's emerald dragonfly was first proposed as an endangered species in October 1993. The U.S. Fish and Wildlife Service cited three main reasons why Hine's emerald warrants federal protection. Fragmented habitats and small, highly-distributed populations were significant concerns. The Recovery Plan by the U.S. Fish and Wildlife Service was published in 2001. This land is concentrated in various counties in Illinois, Michigan, Missouri, and Wisconsin. This proposal considered the exclusion of all Missouri populations and two from Michigan. The 2010 ruling doubles the critical habitat range for HED. Threats The Hine's emerald dragonfly recovery plan was published in 2001. At that time, the major threats to the species were habitat loss/alteration and contamination. Hine's emerald dragonflies inhabit marsh and wetland habitats, which are already rare. Further loss of habitat would disrupt the surviving populations of the species. The recovery plan explains the habitat loss. Industrial, agricultural, and commercial development caused the most damage. This damage contributed to the decline of the species. This is a vital component of Hine's emerald larval habitats. The invasion of species like the common reed may decrease crayfish populations. Thus, decreasing the number of crayfish burrows that are a place of refuge for Hine's emerald larvae. Human impact Humans can impact Hine's emerald dragonflies in a variety of ways. Most human impact involves habitat destruction/alteration. Reduction in habitat area fragments populations. Quarrying, filling wetlands, and creating landfills are examples of harmful human actions. Contamination is another way humans can harm Hine's emerald populations. Landfills have the potential to leach harmful chemicals and contaminate surface and groundwater. Both surface and groundwater are critical to Hine's emeralds in the larval stage. Recreational activities and agriculture may also impact Hine's emerald populations. The insecticides, herbicides, and fertilizers used in these practices could harm Hine's emerald populations. Fertilizers may lead to changes in Hine's emerald habitats that could impact the species. Conservation efforts Hine's emerald is listed on the Federal list of Endangered and Threatened Wildlife and Plants. This means that the species is protected under the Endangered Species Act of 1973 (ESA). Hine's emerald is also listed as endangered in Illinois, Wisconsin, Missouri, and Michigan. This provides the species with State level protections and Federal protections. Habitat protection Many agencies help protect Hine's emerald habitats. State and County agencies protect the habitats of three subpopulations in Illinois. The University of Wisconsin and the Wisconsin Department of Natural Resources (WDNR) help protect Hine's emerald habitats, one such being the Gardner Swamp Wildlife Area. They protect the habitat of the population in Ozaukee County, Wisconsin. The WDNR also protects the habitat of the population in Southwest Wisconsin. The U.S. Forest Service or Missouri Department of Conservation protects Hine's emerald habitats in Missouri. These agencies protect most of the habitats for two of the Missouri subpopulations. State and Federal agencies protect habitats in the Northern Recovery Unit. They protect the habitats of five out of the 16 subpopulations. Groundwater recharge Groundwater recharge areas make an important contribution to Hine's emerald habitats. Researchers have worked to outline the areas that contribute to many Hine's emerald habitats. However, they have not mapped recharge areas for all Hine's emerald habitat sites yet. More research is necessary to identify recharge areas for all Hine's emerald sites. Sections 7 and 9 of the ESA protect all identified groundwater recharge areas. The Illinois Natural Areas Preservation Act protects identified areas in Illinois. == References ==