Rare or Threatened and relative abundance status

[Michael Gochfeld]

In response to the following question 

I would like to know how to categorize abundance of the insect.

Rare or Endangered?

 Is there any link between category like:
 Very common - Common - Very abundant - Abundant - Rare - Very rare -
 Sporadic
 and category like:
 Common - Vulnerable  - Threatened - Endangered - Critically 
Endangered???

The status  "special concern", "vulnerable", etc are conservation status 
categories which have legal or quasi-legal status when it comes to 
conservation and management.  A species may be classified as endangered 
even if it is locally common, if there are only one or two populations 
in a state. 

The other categories: abundance, etc, can be considered categories of 
relative abundance.  We provided a semi-quantitative definition in 
BUTTERFLIES OF NEW JERSEY (p36). 
"superabundant" one may find more than 500 individuals in a given place, 
or a 4JC (fourth of July count) total greater than 2,000"
	This is all relative:  2000 Cabbage White (Pieris rapae) may not 
seemlike much, while 2000 swallowtails would generally be accepted as 
superabundant. 

Abundant: more than 20 at the right time or place or more than 500 on a 
4JC. 

Common: 5-20 in a day and more than 100 on a 4JC

Fairly common   1-4 individuals in a day and more than 10 on a 4JC

Uncommon  1-4 individuals several times in a season, but not daily

Occasionally common.  5-20 individuals in a day but only a few times in 
a season. 

Locally common: "a species that is uncommon, rare or absent in most 
habitats or locality, but common in its preferred habitat" (or in a few 
localities).

Rare.  Not usually seen at any time and place.  Fewer than five times in 
a season and then only one individual at a time.

Irruptive: usually rare or absent, but may occasionally become common or 
abundant. 

We didn't incude vagrant, accidental, or other terms to describe species 
that can NEVER be expected but somehow turn up far out of range.

In reading these definitions written more than a decade ago, I wonder 
whether they should be taken seriously or whether they can be applied 
across species.  For instance 10 Harvesters (Feniseca) would be 
considered abundant in most locations. 

The final answer: I don't think there is much of a relationship 
betweenthe conservation status and the relative abundance. 
I hope that is helpful.  M. Gochfeld

 
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