DESERT TORTOISE SIGN RECOGNITION INITIAL REQUIREMENTS DESERT TORTOISE SIGN RECOGNITION. Find Sign in the Open INITIAL REQUIREMENTS.

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1 PERPENDICULAR DISTANCE PERPENDICULAR DISTANCE Follow Lead Follow Lead INITIAL REQUIREMENTS Know and Understand USFWS Requirements for Desert Tortoise Surveys Download, Read, Understand New USFWS Survey Requirements 100% Coverage Appropriate Time of Year Appropriate Temperatures When Appropriate, Walk Transects in the Zone of Influence Must Find the Project Site Client Must Provide Good Maps and UTM Coordinates Know How to Use Your Equipment (GPS Unit, Thermometer, Maps) INITIAL REQUIREMENTS Find Sign in the Open Concentrate on the Task Minimize Distractions E.g. Talking, Phone Calls, etc. More Difficult Keeping Concentration in Areas of Low Density but it is vital to find some of the few sign that may be available Data From Line Distance Transects Shown that Live Adult Tortoises are Missed When Fieldworkers are Three Meters from Each Other Burrows and Scat are Much More Difficult to Find Must be Able to Recognize Desert Tortoise Sign And Under Cover LINE DISTANCE TRANSECTS - LIVE TORTOISE ENCOUNTERS Top - Tortoises > 180 mm MCL Lower - All Tortoises FREQUENCY Adult Tortoises were Missed at < 1.5 m Live Tortoises more visible than Scats and Burrows At 8 meter intervals about 70% of adult tortoises are located FREQUENCY 1

2 Relative Frequency of Tortoises Found in Burrows and in Open 100% 90% 80% BURROW SHRUB OPEN NOT ALL SIGN ARE VISIBLY EQUAL Easy - Tortoise and burrow RELATIVE FREQUENCY 70% 60% 50% 40% 30% Not so Easy - Trail to burrow, dark scat on cobble 20% 10% 0% FOCAL TRAN FOCAL TRAN FOCAL TRAN FOCAL TRAN FOCAL TRAN FOCAL TRAN FOCAL TRAN Cryptic - Old gray scat on light cobble or dark scat on dark cobble YEAR AND OBSERVATION TYPE SEARCH HABITAT THOROUGHLY SEARCH HABITAT THOROUGHLY Spend 75-80% of search time within 2.5 meters Tighten interval between searchers as needed Search in front and behind you Search under and thru shrubs Keep search image of tortoise, scat, and burrow shapes in mind CONCENTRATE! SEARCH BURROWS THOROUGHLY BE CAREFUL! Do what is necessary to search burrows thoroughly Use bright flashlight or mirror Use probe if needed (if you have your Permit!) 2

3 LOW DENSITY AREAS Never assume tortoises are not present! Always be diligent Fewer rewards but of no less importance Your confidence will be deflated now and then TYPES OF SIGN IN ORDER OF FREQUENCY Scat Burrows Carcasses Live Tortoises Drinking Depressions Tracks Eggs or Eggshell Fragments Shaped like a short cigar May be straight, a crescent, tapered ends or not, but not serrated or twisted Material generally largenot chewed Material generally oriented linearly SCAT Variety of colors Age from dark to light Aging: Current year/not Current Year GEOPHAGUS SCAT IS IT TORTOISE? Top - Chuckwalla Bottom - Desert Iguana Check: Odor, Shape, Particle Alignment, Location 3

4 OR IS IT NOT TORTOISE? Top - Sheep SHEEP Typically in Flocks Large Areas of Impact Bedding Areas and Many Scat Bottom - Burro Check: Particle size and alignment, shape BURROW Shaped like a half-moon Flat bottom Sides angle directly from the floor Well-rounded, clean (no rocks) mound Class 1 - Active: tortoise or tracks present BURROW CLASSES Class 1 - Active: tortoise or tracks present Class 2 - Good: No structural degradation, a tortoise could just walk in BURROW CLASSES 4

5 Class 3- Poor: Substantial structural degradation, much effort needed to use the burrow BURROW CLASSES Class 4 - Good condition Class 5 - Poor condition BURROW CLASSES POTENTIAL TORTOISE IS IT A TORTOISE BURROW? Yes! - Look back in the tunnel for the actual shape - or for a tortoise IS IT A TORTOISE BURROW? Fox Burrow Trail on mound and into burrow Vertical rise at base Tracks IS IT A TORTOISE BURROW? Badger Burrow Claw marks on burrow walls Vertical rise at base IS IT A TORTOISE BURROW? Kangaroo Rat burrow - in sandy soils the sides collapse 5

6 JUVENILE TORTOISE BURROW May use rodent burrows when very small Will dig their own burrows when very young Check for tracks in tunnel Search surrounding area for more burrows and tortoise TORTOISE TRACKS Seen only in soft soil Two rows of footprints Use toenail marks to determine direction of travel GEOPHAGUS SITES GEOPHAGY SITES Often under surface of desert pavement Or along washbanks Often under surface of desert pavement Soil on beak will be dry and not embedded in scales DRINKING DEPRESSIONS Always in areas with fine soils Commonly at base of a rock Tortoise will eat mud or suck up water thru nares Not in typical sandy or loam soils 6

7 Size of ping pong balls Are oval, round, or elongate TORTOISE EGGS May be in the open Generally associated with a burrow TORTOISE NESTS CARCASSES Two Main Objectives Estimate Time Since Death Determine Cause of Death Amount of Disarticulation of Scutes or Bones has Nothing to do with Time Since Death Look Thru Coyote Scats 7

8 TIME SINCE DEATH Based on amount of weathering of scutes and bones Use most weathered portions Categories < 1 year (all parts have sheen and luster) 1-2 years (bones and scutes faded, no luster) 2-4 years (scutes faded, may be cracked and curling; bones faded, may be pinholes or superficial cracks > 4 years (scutes very weathered, bones deossifying, layers of collagen cracked and peeling) Juveniles age more rapidly than adults, in a separate portion of the key Note lack of ossification Completely ossify at 7 to 10 years (90 to 110 mm) Less than one year time since death Left - < 1 year (bones, scutes, and scales are glossy) Right years (scutes, tightly adhered, are fading 8

9 Look at situation prior to intrusion Search entire site, parts may be scattered Most will be unknown CAUSE OF DEATH 9

10 Left - Entrance wound Right - Exit wound, note concoidal fracture 10

11 LIVE DESERT TORTOISE Size Sex Health Status Weight Parasites URTD Signs Shell/bone Abnormalities Injuries No Permit - No Harrass!!! CARAPACE Nuchal Marginals (11 each side [Peripherals]) Pygal Costals (4 each side) Vertebrals (5) PLASTRON Gulars Humerals Pectorals (Pleurals) Abdominals Femorals Anals LENGTH WEIGHT Length = MCL Maximum or Midline Carapace Length Straight-line distance from nuchal to pygal Use medium-weight string, dental floss, plastic bag, etc. Always keep hand under the tortoise Pesola scales are the most consistent Long throw for accuracy 11

12 Sterilize all equipment that contacts tortoise Use 20% solution (bleach or chlorinebased solution) STERILIZE MALE Long Tail Concave Plastron Long Gular Usually Larger Chin Glands Change solution weekly FEMALE Short Tail Flat Plastron Short Gular Longer Rear Nails Small Chin Glands HATCHLING Hatchling Plate or Areola Gray Material is New Growth JUVENILE Few Growth Annuli Note New Growth from Previous Spring Annuli deposition is when a tortoise grows, not annually 12

13 ANOMALOUS TORTOISE 13

14 EXTERNAL PARASITES INJURIES Have Nothing but Time and Energy Substantial Risk to Desert Tortoises Other Wildlife And People DOGS 14

15 IN CONCLUSION Thank you Know and Recognize Sign CONCENTRATE - Sign is easy to miss Recognize Normality - Behaviors, Morphology, Health Signs Document Photograph Ask Questions (USFWS, CDFG, BLM) Distribute Data and Information 15