Chapter 5 Threats
The most commonly occurring groups of freshwater algae are diatoms, green algae, and blue- green algae, which are more correctly known as cyanobacteria. Cyanobacteria refer to a group of microorganisms that possess characteristics of algae (chlorophyll- a and oxygenic photosynthesis). They are found in fresh, estuarine, and marine waters in the United States and cyanobacterial blooms can produce highly potent cyanotoxins (USEPA 2014) . In North Carolina, two cyanobacteria—Blue-green and Black Mat Algae ( Lyngbya spp.)—are of particular concern because they produce neurotoxins and paralytic shellfish-poisoning toxins (USEPA 2014) . Invasive and nonnative aquatic plants like Watermilfoil and Hydrilla are economically damaging aquatic weeds (Richardson 2008) and can form dense mats that can clog boat motors and make swimming difficult. Propagation of Hydrilla invades via tubers, turions, plant fragments, and stolons, and is likely spread between lakes by plant fragments attached to boats (Harlan et al. 1985) . In locations where Hydrilla mats do not survive winter temperatures, regrowth can occur from residual tubers and turions and germinate in the spring (Harlan et al. 1985) . Public awareness of the need to clean recreational equipment such as boats, watercraft, and trailers as well as fishing tackle and gear should be a high priority. Information is available online on proper techniques for cleaning equipment to reduce or prevent the spread of aquatic, invasive species (see https://stopaquatichitchhikers.org for specific procedures). Exotic or invasive aquatic snails in the state include Chinese Mystery Snail, Creeping Ancylid, Giant Rams-horn, Japanese Mystery Snail, Red-rim Melania, and Savannah Elimia. The Red-rim Melania is a host for parasitic trematode worms (e.g., liver flukes and lung flukes), which allows the flukes to complete their life cycle. Trematode flukes affect waterfowl, fish, and other animals and can be transmitted to humans who eat raw or undercooked fish or crab that have been infected or who swim in waters that contain the flukes (Wingard et al . 2008) . Although not currently extant in North Carolina, Zebra Mussels, Bighead Carp, and Silver Carp occur in adjacent states and pose extremely high risks to our aquatic ecosystems. These species are known to alter community dynamics and even extirpate other species. 5.10.2 Terrestrial Systems – Anticipated Impacts The results of some studies suggest the synergistic effects between climate warming and the presence of invasive species will negatively affect many wildlife species (Saenz et al. 2013) . Some studies indicate amphibian declines may be attributed to invasive species becoming established in their habitats (Saenz et al. 2013; Doubledee et al. 2003; Brooks et al. 2004; Brown et al. 2006) . The NC Department of Transportation identifies 74 species in a guide to invasive or exotic trees, shrubs, herbaceous plants, vines, and aquatic plants that are considered a threat, moderate threat, or a watch-list concern in the state. The plant species described in this guide should be considered a priority when addressing problems caused by invasive, introduced, or exotic plants. The guide provides recommendations for management and treatment options as well as resources for additional information and is available for download as a PDF document (see
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2025 NC Wildlife Action Plan
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