Brix Index
An index highly correlated to the protein levels present in lobster blood. This index is measured via a Brix refractometer which is actually designed to measure sugar contents in liquids by assessing the refractivity of the light in the sample of liquid assessed. Although Brix refractometers are not designed to measure blood proteins, the Brix index (for sugar) is highly correlated to protein levels, and therefore, Brix refractometers are a inexpensive alternative to the traditional refractometers used in human or veterinary medicine. (View a graph showing the relationship between protein levels and the moult cycle.)

Carapace Length (cl)
The carapace length is a measure of the size of the lobster. It is measured in millimeters, from the back of the eye socket to the end of the carapace, on the back of the lobster. The carapace length is the size measurement used for regulation purposes.

Mean
The mean is an arithmetic value that is computed by dividing the sum of a set of terms by the number of terms. The mean is often referred to as an average.

Median
The median is a value in an ordered set of values below and above which there is an equal number of values. In other words, 50 % of the values are above and 50 % are below the median in an ordered dataset. The median is usually more useful than the mean when summarizing a dataset in which a few values are either very high or very low (eg A few jumbo lobsters in a crate of 1.5 lbs lobsters will bring the mean weight up but not the median).

Moult Stage
The moult cycle can be differentiated into a series of five stages from A to E, based on physiological and changes in the composition and appearance of the shell. In this project, premoult stage refers to the sub-stages of Stage D of the moult stage which can be assessed by examining the tip of a pleopod (swimmeret) with a microscope. Stage A accounts for approximately 2% of the entire moult cycle, Stage B for 8%, Stage C accounts for 15 to 65 % while Stage D accounts for 25 to 75 %. Finally, Stage E lasts less than 0.01% of the entire moult cycle. Stage D is divided into five sub-stages, and is referred to as the premoult stage and accounts for 25 to 75% of the moult cycle. In this project, the premoult stages have been grouped as follows:

Stage 0: Postmoult or intermoult
Stage 1.0 to 2.5: Passive premoult
Stage 3.0 to 5.5: Active premoult (irreversible stage; lobster is committed to moult)

(View a graph showing the relationship between protein levels and the moult cycle.)

n
Sample size. The number of lobsters assessed.

SD (Standard Deviation)
The standard deviation is the most commonly used measure of statistical dispersion. Simply put, it measures how spread out the values in a data set are. The lower the standard deviation is, the more uniform the data are in their values.

Sex
Sex is defined as either male, female or berried females (female lobster with eggs under their tails).

Shell Hardness
This parameter is a subjective assessment of how hard the shell is. Shell hardness is recorded either soft, medium or hard. The characteristics for each category are as follows: