Scanning for existing tags
1.There is no consensus on the placement of PIT tags, and for this reason
project personnel should examine all possible sites (i.e. left and right
shoulder muscle, left and right fore flippers, left and right rear flippers,
neck) for existing tags before a new tag is inserted. Be sure to scan all
areas, even if a PIT tag is found, because some turtles may already have
more than one PIT tag.Protect the reader under field conditions by placing
it in a clear and durable plastic bag.
2.To scan for an existing tag: turn the reader ON , place the reader
directly on the skin of the turtle to decrease the “read distance”,
and then press and hold the READ button.
3.Continue to hold the READ button while moving over the area to be
scanned in a circular motion. Be sure to use the entire reading surface
of the scanner when trying to detect the tag.
4.After you have made a number of scans of the area, re-scan the area
while tilting the scanner at various angles. PIT tags read best when the
tag is pointing with the small end (picture the tip of a grain of rice)
pointed directly toward the scanner, but the tag is not always oriented
optimally under the skin. By tilting the reading surface at different
angles during a sweep, you improve your chances of detecting a tag
that may be angled away from the skin.
5. If a PIT tag number is identified by the reader, the number should
be entered on the data sheet in the space allocated for this type of tag,
and should be documented EXACTLY as it appears on the scanner
display, including any hyphens that may appear as part of the code..
Double-check to make sure you have recorded the tag “number”
exactly as it appears on the reader display, taking care concerning
letters and numbers that can easily be confused, e.g. the letter O and
the number 0 (or, Ø).. Remember also that if the turtle, or flipper, is
resting on anything iron (such as the bed of a truck), you should lift it
up a few inches before reading. Iron (and certain neon lighting and
electrical motors nearby) can neutralize the ability of the reader to
detect a tag.
6.Once you confirm that the turtle is not already carrying a PIT tag,
prepare a new tag for insertion.
Physical examination of turtle to be tagged
a.The Turtle should be examined and observations recorded prior
to tagging.
• Sex
• Demeanour/activity/behaviour of the unrestrained animal should
be assessed
• Respiratory rate and effort should be gauged without excessive
handling
• The shell should be examined e.g. for softness and evidence of
infection of septicemia
• The skin should be examined for lesions and abnormalities such
as abscesses sores swellings and oedema.
• The limbs should be examined and compared - if possible, but
this can be difficult in an aggressive healthy sub-adult
• The eyes should be examined and a basic assessment of visual
ability made
• The oral mucosa should be assessed. However this may only be
possible if the animal opens its mouth and gapes in a threat
response to the clinician
Where it is felt that an animal is in inadequate health to receive a
microchip, tagging should not be proceeding.
b. Measurement of turtles prior to be tagged
• Straight Carapace Length (SCL)
• Straight Carapace Width (SCW)
• Plastron Length (PL)
• Body Weight
PIT TAG (Passive Integrated Transponder)
In General
1. PIT tagging should only be done under the guidance of workers
experienced with the technique.
2. A PIT tag is injected under the skin, generally into muscle,
using a needle applicator provided by the manufacturer. PIT
tags and applicators are pre-sterilized and packaged for field
use. If the PIT is not pre-sterilized, it is important that
each tag be soaked in a nontoxic sterilizing solution (such as
alcohol) prior to use. Only one PIT tag be applied per animals.
3. Turtles smaller than 30 cm SCL will not be PIT tagged.
4. For nesting turtles, a pre tagging procedure of scanning for
existing tags must be done before applying one.
To be able to recognize individuals.
To understand Biology
Where they go to feed?
How do they reproduce?
Where are their migration routes?
To be able to estimate their population status.
To determine the success of "in-situ" (on site, original nests) and relocated nests.
Monitor deaths and strandings.
To monitor growth rates and age
