Hamline University Graduate School St. Paul, Minnesota Frogs as Bio-indicators Joan Chadde, MI Technological University Tony P. Murphy, Hamline University Kristin Schuster, Houghton Middle School

Hamline University Graduate School St. Paul, Minnesota What are we being told by: Amphibian (frog and toad) malformities Amphibian populations locally and globally But first……

cold blood smooth or slimy skin warty and dry skin strong, long legs and stubby bodies with short webbed hind feet hind legs two bulging eyes parotid glands behind eyes lay eggs in clusters lay eggs in long chains a group of frogs is called a group of toads is called an ARMY of frogs a KNOT of toads Vs. Frogs have:Toads have:

Anuran Diversity

14 species in MN, 13 species in MI Frogs and Toads 92 species in USA 3,300 species in the world

MN Frogs and Toads

Why We Care 1.Anurans are a part of the planet’s bio-diversity. 2. Anurans interact in interesting ways with each other and the environment, i.e. both prey and predators

Why We Care 3. Anurans provide benefits to humans i.e. Gastric Brooding Frog of Australia might have provided answers for people suffering from gastric ulcers (Case of the Vanishing Frogs, T. Halliday and W. R. Heyer).

4. Frogs As Bio-indicators 1) double life--amphibious 2) permeable skin 3) absorb and concentrate toxins-- biomagnification

4. Frogs As Bio-indicators Biomagnification: a process in which retained substances become more concentrated with each link in the food chain

Malformed Amphibians

External Malformations extra or missing limbs branching limbs spikes or protuberances missing eyes abnormal webbing

Internal Malformations reproductive digestive urinary

Malformed Frog Pictures

Dr. David Hoppe, University of Minnesota-Morris

Causes of Malformations genetic origins parasite disruption of limb formation chemical contamination viruses ultraviolet radiation physical trauma (predation, people)

Trematode (flatworm) cysts have been demonstrated to cause problems in limb bud development in tadpoles Dr. Stanley K. Sessions, Hartwick College

Possible Chemical Contaminants agrochemicals heavy metals acid rain chlorofluorocarbons (CFCs)

Types of Agrochemicals herbicides Maneb-fungicide pesticides propylthiourea fertilizers Dr. Stanley K. Sessions, Hartwick College

Types of Agrochemicals applications of the herbicide atrazine have led to egg mortality and tadpole deformities (Hazelwood 1970) Dr. Stanley K. Sessions, Hartwick College

Where have all the frogs gone? Global Anuran Decline a concern during the past decade frog declines widespread and well- documented possible causes include habitat destruction, increased UV radiation, and chemical contamination

Global Population Declines Loss of habitat from filling in wetlands to create more farmland for crops, and to build more houses and roads (Case of the Vanishing Frogs, T. Halliday and W. R. Heyer).

Global Population Declines Increasing ultraviolet radiation Pollution by chemicals Acid rain Pathogens Parasites Introduction of non-native species