Species Prioritization in Arizona’s Aquatic Invasive Species

Management Plan-2012. Dr. David Walker

University of Arizona

Difficult and often subjective. Animals, plants, and algae.

• Human health• Human infrastructure• Commerce• Recreation• Ecological impact to native or economically valuable species• Environmental health• Intrinsic value of native wildlife

Potential Impacts and Threat Score

Priority given to species that are the most abundant and negatively impacting Arizona.

Those species with distributions having little impact versus wide distributions posing extra management challenges will weigh on prioritization as well.

“Priority of threat analysis”, given to species not yet found in Arizona. ◦ Focus of early detection and rapid responses for

emerging AIS populations in the state.

Relative Abundance

• Prevention (outreach, education, enforcement)• Early detection, rapid response (EDRR)• Containment/control• Eradication – localized• Management (no eradication possible)

- Prevention of spread

- Minimization of impacts

Actions to be Considered

“AIS whose introduction and spread has already caused, or has the potential for, significant impairment of a water body (or water bodies) within the state for either anthropocentric use or intrinsic value.”

“Efforts at containment through prevention of introduction of species are likely to have the greatest environmental and/or economic impact.”

Priority 1Species

• Giant salvinia (Salvinia molesta)• Golden algae (Prymnesium parvum) • Hydrilla (Hydrilla verticillata) • New Zealand mud snail (Potamopyrgus

antipodarum)• Quagga mussel (Dreissena rostriformis

bugensis)• Silver carp (Hypophthalmichthys molitrix)• Whirling disease (Myxobolus cerebralis)• Zebra mussel (Dreissena polymorpha)

“AIS whose introduction and spread may have, or has the potential to impair a water body or bodies within the state, detracting from either anthropocentric use or intrinsic value.”

“These AIS do not currently have as great a potential for wide-spread harm to aquatic systems as Priority 1 AND/OR their presence in the state has only been anecdotal”

Priority 2

“They are highly localized so that spread appears relatively minimal AND/OR the introduction and potential spread of these AIS, and subsequent impairment, appears to be imminent or great.”

“Priority 2 consists of populations which might be controlled locally.”

Priority 2 (cont.)

• Bighead carp (Hypophthalmichthys nobilis)• Chytrid fungus (Batrachochytrium dendrobatidis)• Didymo a.k.a. “rock snot” (Didymosphenia

geminata)• Eurasian watermilfoil (Myriophyllum spicatum)• Northern snakehead (Channa argus)• Purple loosestrife (Lythrum salicaria)• Redclaw crayfish (Cherax quadricarinatus) • Rusty crayfish (Orconectes rusticus)

“AIS whose introduction and spread within the state seems minimal compared to Priority 1 or Priority 2 AIS, however, the potential for introduction and spread exists AND/OR these AIS have already caused large-scale impairment to aquatic systems in Arizona but have become so firmly entrenched or wide-spread throughout the state that currently the management, remediation, and control of these AIS seems infeasible or is otherwise logistically difficult or impossible.”

Priority 3

• Asiatic clams (Corbicula spp.)• Bullfrog (Rana catesbeiana)• Giant reed (Arundo donax)• Golden apple snail (Pomacea canaliculata)• Nutria (Myocastor coypus)• Northern crayfish (Orconectes virilis)• Round goby (Neogobius melanostomus)• Viral hemorrhagic septicemia (order Mononegavirales, family Rhabdoviridae, genus Novirhabdovirus)

Although this is the prioritization scheme as it stands today, the Arizona AIS Management Plan is meant to be a working document.

Species will undoubtedly be added or subtracted, or prioritization changed, as threats rise and fall.