As igelkott says a HoA is the way to go. It looks as though monkey is the record separator. Setting Perl's record separator might help. 
#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;
$Data::Dumper::Indent = 1;

$/ = q{monkey};
my %hash;
while (<DATA>){
  my ($country, $fox_hour) = /forest\s+(\w+).*-fox\s+(\d{4})/s;
  next unless $country;
  push @{$hash{$country}}, $fox_hour;
}

print Dumper \%hash;

__DATA__
forest France
-wolf
-toad
-fox 1350

monkey

land
-dog
-cat
-slug

forest France
-deer
-swan
-fox 1426

monkey

forest USA
-deer
-swan
-fox 1560

monkey

[download]
outputs 
$VAR1 = {
  'France' => [
    '1350',
    '1426'
  ],
  'USA' => [
    '1560'
  ]
};

[download]
update: added link

In reply to Re: add values with hash by wfsp
in thread add values with hash by steph_bow

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