Sea Temp

I have noticed over the last two weeks that mackerel seem to be getting harder to get. Also triggers do not seem to be around in the numbers they were last year.
I just compared the sea temp to this time last year and it is a full 2 degrees lower, currently at 14.5.
Are the summer species moving out ?

the way some people are talking they never moved in in the first place this "summer"

also with all the fresh water being pumped in it may have something to do with it too

maybe