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Wildlife Marking Techniques. Marker Selection. Desirable marker characteristics are those that: cause minimal pain or stress. have no negative effects on survival or behavior. have good retention. are easy to recognize. are easy to apply. are easy to obtain and assemble. are inexpensive.
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Marker Selection • Desirable marker characteristics are those that: • cause minimal pain or stress. • have no negative effects on survival or behavior. • have good retention. • are easy to recognize. • are easy to apply. • are easy to obtain and assemble. • are inexpensive.
Marker Retention • Three main types of markers: • temporary • semipermanent • permanent
Recognition • Colors-bright colors that contrast with animal • Numbers-must be able to recognize and read digits • Placement site (e.g., left ear) • Know your animal…use an appropriate marker for the species and habitat.
Be Aware of Possible Adverse Effects 1. Icing on nasal tags or neck collars 2. Catching legs in collars 3. Too heavy for species that fly 4. Too large for species that regularly use holes in trees, rocks, or burrows.
Questions to ask: • Can study objective still be met or will data be biased? • What are the limitations of the data caused by effects of marker on animal and how will these be handled during analysis? • Does the information obtained outweigh the adverse effects of the marked population if study objectives are met? Appropriate Techniques
Marking Techniques for Mammals • Ear, web, and flipper tags • Most wildlife studies double tag or double mark in some way. • Small metal ear tags have high retention. • Large cattle ear tags—can use colors and numbers for individual recognition.
Neck Collars • Colors for individual recognition • If radio collars, color or band is generally white or brown. • Some use colored tape to create unique markings • Species specific and generally works for larger mammals
Arm or leg bands Have been used on bats Tapes, streamers, bells Have been used to mark mammals These types of markers are of short duration Marker lose can be high or damage can effect marker
Transponders Chips uniquely programmed with a code >34 billion code combinations are available
Mutilation Branding: Hot branding not used—freeze branding or Cryo-branding Tattoos:Commonly used on large mammals-upper lip or ear Tissue Removal:Toe and ear clipping used on small mammals
Dyes and Paints Short duration marking External vs. internal Hair dye, nyanzol— external marking Picric Acid not available for external marking Rhodamine B--acts as internal marker
Markers Particle Markers: Flourescent pigments, plastic particles have been used to estimate home range of small mammals Chemical Markers:Demethychlorotetracycline—marks bones Radioactive Markers—no longer available Natural Markers—e.g., pronghorn, giant river otters, African lions, leopards
Marking Techniques for Birds Leg Bands: Types include butt-end, rivet, laminated plastic, anodized aluminum colored, soft plastic wrap-around. Butt-end or split ring most common leg band Main causes of band loss: Abrasion and corrosion from salt water and defecation Some geese have retained leg bands for > 20 years
Information on bands along with species marked is reported to the migratory bird banding laboratory in Laurel, Maryland. Also known as: Patuxent Wildlife Research Center
Wing markers: Generally made from flexible PVC-coated nylon fabric Tag loss low first year but increases in later years Neck bands: Used extensively to mark geese-also used other birds Can disrupt pair bonds, can ice in northern latitudes
Tags Nasal tags, back tags, web tags Best tag is dependent on bird species, type of information required, and how long you need the mark to last.
Mutilation Feather clipping Tissue Removal-toenail clipping, tissue punch Tattooing: usually placed on underside of wing/body skin Freeze Branding: ducklings? Dyes, Paints, and Inks: similar both birds and mammals Picric Acid??
Feather Imping?? What is it. Particle, Chemical, and Radioactive Markers: Demethychlorotetracycline Nocturnal Tracking Lights Betalights-small lights that can be used to visually track bird movements Natural Markings: less common for birds than mammals
Marking Techniques for Amphibians and Reptiles External Markers Branding-Freeze branding-mark cannot be read until after animal sheds Hot Branding similar to toe clipping for survival Chemical Branding-silver nitrate commonly applied Laser Marking—does it work?
Tattoos—has been used with frogs Tissue Removal Toe or tail clipping has been used Skin transplantation 95% success rate for grafts and retention was >3 years
SURVIVAL ANALYSIS FROM BANDING DATA DEFINITION OF PARAMETERS S = SURVIVAL RATE OR PROBABILITY OF SURVIVING THE YEAR K = KILL RATE OR PROBABILITY OF BEING KILLED BY A HUNTER DURING THE YEAR H = HARVEST RATE OR PROBABILITY OF BEING KILLED AND RETRIEVED BY A HUNTER DURING THE YEAR 1 – S – K = NONHUNTING MORTALITY RATE LAMBDA = BAND REPORTING RATE = PROBABILITY THAT A HUNTER WILL REPORT THE BAND GIVEN THAT HE HAS KILLED AND RETRIEVED A BANDED BIRD c = RECOVERY RATE OR THE PROBABILITY THAT A BIRD IS SHOT AND THE BAND REPORTED.
POTENTIAL FATES OF A BANDED BIRD ALIVE AT THE START OF THE YEAR THE BANDED BIRD CAN: 1. SURVIVE 2. BE KILLED BY A HUNTER IF KILLED BY A HUNTER THE BIRD CAN: a. NOT BE RETRIEVED b. BE RETRIEVED AND THE BAND NOT REPORTED c. BE RETRIEVED AND THE BAND REPORTED 3. DIE FROM NATURAL CAUSES
ASSUMPTIONS INVOLVED IN MAKING INFERENCES FROM BANDING DATA 1.THE SAMPLE IS REPRESENTATIVE OF THE TARGET POPULATION 2. AGE AND SEX OF INDIVIDUALS IS CORRECTLY DETERMINED 3. THERE IS NO BAND LOSS 4. SURVIVAL RATES ARE NOT AFFECTED BY THE BANDING OR TAGGING ITSELF 5. THE YEAR (HUNTING SEASON) OF BAND RECOVERIES IS CORRECTLY DETERMINED
ASSUMPTIONS OF BANDING ANALYSES, CONTINUED. 6. THE FATE OF EACH BANDED BIRD IS INDEPENDENT OF THE FATE OF OTHER BANDED INDIVIDUALS 7. ALL BANDED INDIVIDUALS OF AN IDENTIFIABLE CLASS (AGE OR SEX) IN THE SAMPLE HAVE THE SAME ANNUAL SURVIVAL AND RECOVERY RATES 8. ANNUAL SURVIVAL AND RECOVERY RATES CAN VARY BY CALENDER YEAR, AGE, SEX, AND AREA
SUPPOSE THAT WOOD DUCKS ARE BANDED JUST PRIOR TO THE HUNTING SEASON FOR TWO YEARS c1 = RECOVERY RATE YEAR 1, THE PROBABILITY THAT A BIRD IS SHOT AND ITS BAND IS REPORTED DURING THE FIRST YEAR c2 = RECOVERY RATE YEAR 2, THE PROBABILITY THAT A BIRD, ALIVE AT THE BEGINNING OF THE HUNTING SEASON IN YEAR 2, IS SHOT AND ITS BAND IS REPORTED S1 = THE PROBABILITY THAT A BIRD SURVIVES FROM THE BEGINNING OF THE FIRST HUNTING SEASON TO THE BEGINNING OF THE SECOND HUNTING SEASON
IF 1,603 BIRDS ARE BANDED IN YEAR 1, WE EXPECT 1,603 BIRDS x c11 TO BE SHOT AND REPORTED THE FIRST YEAR THAT ACTUAL NUMBER WAS 127 AN ESTIMATE OF c11 THEN BECOMES 127/1,603 = 0.0792 OF 1,595 BIRDS THAT WERE BANDED IN YEAR 2, WE EXPECT 1,595 x c21 TO BE SHOT AND REPORTED THAT ACTUAL NUMBER WAS 62 SO, AN ESTIMATE OF c21 BECOMES 62/1,595 = 0.0389
OF THE 1,603 BIRDS BANDED THE FIRST YEAR WE EXPECT 1,603 x S1 TO SURVIVE TO THE BEGINNING OF THE HUNTING SEASON IN YEAR 2 AND c12 OF THEM TO BE SHOT AND REPORTED THE ACTUAL NUMBER WAS 44 SO, 44 = 1,603 x S1 x 0.0389 OR S1 = 0.7056