Weights & Measures

When collecting standard weights and morphometric (physical) measurements from an animal standardization is key to good data collection. When you consider that thousands of people all over the United States and even across the globe collect these measurements, the only way they are useful is if standard techniques are used by all!

A good rule of thumb is to learn the correct way to take the measurement (e.g. straight length is from tip of rostrum to fluke notch in a cetacean) then come up with a routine for level A data collection and morphometric measurements and do it the same way each time. This routine, especially when adopted by all stranding members within a network, helps ensure accurate, consistent data is collected from each and every carcass.



Below you will find examples of the most common weights and measures that are collected from a carcass.  CLICK on an image to see an enlarged view.

Weights Measures 01   An important part of the necropsy is a good EXTERNAL EXAMINATION, including collecting and recording a series of standard EXTERNAL MEASUREMENTS, such as TOTAL LENGTH, GIRTH, FLIPPER LENGTH and BODY WEIGHT. 
02-weights-measures   When WEIGHING large marine mammals, careful rigging is important. ALSO, keeping the carcass low while weighing is best, in case the support system fails during weighing.

QUESTION: Compare the weighing techniques used here to the next photograph. Which is safer?
03-weights-measures   SAFE RIGGING for WEIGHING a large sea lion using a HANGING SCALE. Note that the carcass is kept CLOSE TO THE GROUND, and MULTIPLE LOOPS of good quality rope are used to distribute the body weight.
04-weights-measures   Normally weights, lengths and other measurements are recorded using a METRIC SCALE (eg kilograms, centimeters, millimeters, etc.).
05-weights-measures   Here measurements of the TEETH are being taken using CALIPERS, which are used for small, precise measurements.
06-weights-measures   TOTAL LENGTH is measured as a straight distance (in CENTIMETERS) from the tip of the nose to the fleshy tip of the tail.
07-weights-measures   AXILLARY GIRTH should be measured (in centimeters) with a tape measure pulled snugly around the chest at the level of the XYPHOID (bottom of the ventral chest bones)
08-weights-measures   FLIPPER LENGTH is measured from the longest tip to the inside connection with the body wall.
09-weights-measures   HIND FLIPPER LENGTH is measured from the tip of the longest toe to the point of attachement to the body, as shown.
10-weights-measures   BLUBBER DEPTH can be checked at multiple locations, but the standard measurement (in MILLIMETERS or CENTIMETERS) is taken during the initial necropsy cut on the ventral midline on the upper chest between the flippers. This photo depicts a sea lion with a thin blubber layer.
11-weights-measures   COMPARE the BLUBBER DEPTH of the previous sea lion with this one! Use care to measure only blubber thickness, without inclusion of the similarly colored skin layer.
12-weights-measures   Don't forget to CONTINUE THE MEASUREMENTS AS YOU COMPLETE THE NECROPSY! Organ weights and measurements (in 3 dimensions: length, width and height) can be very helpful in determining whether organs are enlarged, too small, or are otherwise abnormal.