Many people on the beach holding a very large net.
The people are a part of a native tribe mending their fishing nets.
That people have a net does not imply that they are mending the net or that the net is a fishing net.
Many people on the beach holding a very large net doesn't imply that they are a part of a native tribe mending their fishing nets.
The people aren't necessarily part of a native tribe, and can be holding a net without mending it.