How a dry summer regularly attracts northern chaps catching crabs? (7)

I believe the answer is:

oarsmen

I'm a little stuck... Click here to teach me more about this clue!

'how a dry summer regularly attracts northern chaps catching crabs?' is the definition.
I can't tell whether this defines the answer.

'how a dry summer regularly attracts northern' is the wordplay.
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
'attracts' means one lot of letters go next to another.
'northern' becomes 'n' (abbreviation e.g. N. Ireland).
'how'+'a'+'dry'+'summer'='howadrysummer'
The alternating letters of 'howadrysummer' are 'oarsme'.
'oarsme'+'n'='OARSMEN'

Can you help me to learn more?

(Other definitions for oarsmen that I've seen before include "Crew - moaners (anag)" , "possibly eight in a row" , "Rowing types" , "A sermon about rowers" , "Strokes" .)

I've seen this clue in The Telegraph.

Want a hint initially instead of a full solution? Install my app