Do these two phrases have the same meaning?
Both phrases allude to "something easy to do", but they are used in different contexts, for the most part.
One context for "low hanging fruit" is any discussion of prioritization of tasks, projects, etc. In such a context one often hears of dispatching the "low hanging fruit" first, i.e. giving priority to the easier tasks or projects.
One also comes across the phrase "low-hanging fruit" in something like "all the low-hanging fruit have already been picked", which is a conventional explanation often given for why it is more difficult today than at some earlier time to make a noteworthy contribution in some field of creative activity.
On the other hand "like shooting fish in a barrel" is used as a synonym for "laughably easy to do". Therefore, it is most often used to diminish the apparent merit of some achievement. E.g. A: "She does the Metro's crossword puzzle every day!" B: "The Metro's? *snort* That's like shooting fish in a barrel..." Or "The governor's political gaffes are never-ending, and journalists lost interest in reporting them when they realized it was like shooting fish in a barrel."
There are some contexts in which both phrases can fit, but they carry slightly different connotations. For example, among theoretical physicists one may come across a statement like "In the early days of quantum mechanics, doing research in QM was like shooting fish in a barrel—even second-tier physicists could publish seminal papers. Nowadays, however, it's much harder: all the low-hanging fruit have been picked!"
First, it's not "firing," it's "shooting."
Second, they are not grammatically equivalent, so they cannot be used in exactly the same way.
Given both of those corrections, however, there are similarities.
"Low-hanging fruit" refers to goals that are easily achieved.
"Shooting fish in a barrel" means attacking targets which are easily attacked because they are so vulnerable.
So you can see the similarities, but when you break them down into their actual meanings, you can see that they are not equivalent, and cannot be used in the same way.
Let me give you two very broad examples to help you see the point.
If a person wanted to accomplish running the hundred meter dash in twenty-five seconds, you could say he is certainly going after low-hanging fruit.
If your coworker in a high tech company said, we really should make sure to empty our garbage cans twenty times a day and not make the janitors do it, and you said, I think that might be a waste of our time, don't you think? And of course everyone agreed with you. Then someone could say about your comment, well, that was like shooting fish in a barrel.
I have a strong sense of Deja-vu here:
Anyway They both mean something is easy.
Low-hanging fruits are easy to pick, so they are separate goals that are easy to achieve. Going for low-hanging fruit denotes some lazyness
Shooting fish in a barrel is the correct idiom and it means that whatever is like shooting fish in a barrel is so easy - you will certainly hit a fish - that you are guaranteed to get result - but you do not care which fish you hit
So the difference is the object.
For example (I may find better ones)
- He was lazy so he grabbed all the low-hanging fruit (he decided to only solve the easy problems)
- I know Frank can do better in Math, but by ignoring the algebra and only answering the addition questions, he goes for the low-hanging fruit
- Finding a bug in his code was liking shooting fish in a barrel (there were so many)
- Offending someone in the audience was like shooting fish in a barrel (they were easily offended)
- Hitting the first-graders in dodge-ball was like shooting fish in a barrel (they did not have a clue about spreading out and moving fast)
Low-hanging fruit means that you are taking something easily or doing something that is easy. As a person would grab a piece of low hanging fruit from a tree.
Firing (shooting) fish in a barrel means that you are also doing something easy. It would be very easy to shoot at a barrel full of fish and hit one.
There is a slight difference in meaning. Low-hanging fruit passes more judgement to the person taking the easy piece. They are choosing to do something that is easy.
Firing at fish in a barrel doesn't have that same connotation. It means that whatever you were doing is easy - maybe demeaning the task a little.
Usage: "RyeBread, you only answer the easy English questions. You are going after the low-hanging fruit."
Usage: "Making a layup (mod note: which OP believes to be the easiest shot in basketball) is like shooting fish in a barrel."
Answering this question was low-hanging fruit, not shooting fish in a barrel.