Little Stint/Dunlin numbers mis-understanding

I was at WWT Slimbridge on Sunday.... Out on the South Lake there were about 30-35 Dunlin. Amongst them was 1 much smaller Little Stint (See Photo). When I'm out and about I get to see many Dunlin but hardly any Little Stints. Out of interest I went to the RSPB recognition web Site and surprisingly saw that the Dunlin is Amber Status. The Site shows the population as 360,000 UK Wintering. So I looked up the Little Stint. It is Green Status and only 14 Wintering Birds? Surely the Little Stint should be Amber status and the Dunlin Green Status. Am I missing something here, maybe someone could help explain?...Thank You...Paul