There are places in the world that only Mother Nature comes into play.
Man's direct influence is nominal or non-existent.

With that said, I can see that certain areas were picked over and the big ones
were taken all of the time then they, the big ones would slowly be younger and
thus smaller.

Many of these shells live in waters that are not easy for man to get into.
Depth is one deterrent. For those that mature at depth and come up due to storms;
I tend to believe they will always be large.

Consider the 12 grades in school and the children within.  Lets say 10 grade is
the prime shells and those making it to 11 and 12 are fewer due to trials of life.

If the 10th grade is harvested or picked heavily, then 11 and 12 will be fewer
but the preceding 9 years are coming on as before. It might take a year to recover.

If heavy harvesting or picking that grabs 9,10,11 and 12 - one simply has to wait
a year for the 8th to become a 9th 2, 3 and 4 for the next sizes/ages.

Therefore I propose that unless classes from 1 to 12 are harvested at once, only
floating egg cases can replenish after many years.  The odds are cut down.

[ The worst case is when chemical elements are introduced over a long time and
   these stem the growth or habitat.  Eggs might float in from near by sources,
   but the habitat is destroyed or chemical toxins are still killing the young ]

Otherwise, if a researcher 'samples' during an off year from prior harvesting one
might take the opinion that shells of size 10,11 and 12 are rare and therefore all
classes are then rare.  While in a few years another researcher 'discovers' a
rebirth
of a species based on the first researchers results but finds that year Kindergarten
had grown up and populated the lower grades and starting on the upper grades
over the
time span.

It is a camera effect - this snapshot indicates that snapshot in time and not always
the whole story.

As I recall, the oyster beds off the East coast of North America are controlled and
trolling for them is placed on restrictions after a harvest is made.  Allowing it
to recover for several years.

Martin [ to much math in my mind ]


--
Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH&  Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Originator&  Charter Founder
IHMSA and NRA Metallic Silhouette maker&  member. http://lufkinced.com/

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