Black-headed Gull
Scientific Name: Chroicocephalus ridibundus
Thresholds:
- Lagune du Havre aux Basques et plage de l'Ouest (QC003)133 (max.)
- Quidi Vidi Lake (NF022)105 (max.)
- Île de l'Est (QC009)60 (max.)
- South Shore - East Queens Co. Sector (NS024)50 (max.)
- Plages de La Martinique et de Havre-Aubert (QC005)45 (max.)
- South Shore (Port Joli sector) (NS004)32 (max.)
- La Pointe (QC013)31 (max.)
- Northern Head and South Head (NS053)31 (max.)
- Pomquet Beach Region (NS009)23 (max.)
- Quoddy Region (NB037)22 (max.)
- Gros Morne National Park (NF045)20 (max.)
- Witless Bay Islands (NF002)20 (max.)
- Bassin aux Huîtres (QC015)15 (max.)
- Big Glace Bay Lake (NS007)12 (max.)
- Bird Islands (NS001)10 (max.)
- Brier Island and Offshore Waters (NS021)10 (max.)
- Dune du Sud (QC024)10 (max.)
- PEI National Park (PE013)10 (max.)
- Île aux Loups Marins (QC027)9 (max.)
- Plage de l'Hôpital (QC012)8 (max.)
- Terra Nova National Park (NF017)7 (max.)
- Cap Noir (QC016)6 (max.)
- Cape Freels Coastline and Cabot Island (NF025)6 (max.)
- Grand Bay West to Cheeseman Prov. Pk. (NF038)6 (max.)
- Île aux Goélands (QC021)6 (max.)
- Quaco Bay (NB033)6 (max.)
- The Brothers (NS003)5 (max.)
- Bedeque Bay (PE011)4 (max.)
- Cape St. Mary's (NF001)4 (max.)
- The Cape Pine and St. Shotts Barren (NF015)4 (max.)
Global
1% of the global population estimate. This threshold is used to identify trigger species and IBAs under categories A4i/ii and A4iv.
Regional/Continental
1% of the regional/continental population estimate.
| Lagune du Havre aux Basques et plage de l'Ouest (QC003) | ||
|---|---|---|
| Number | Year | Season |
| 6 | 2021 | Fall |
| 4 - 10 | 2021 | Spring |
| 10 - 25 | 2020 | Winter |
| 5 | 2020 | Fall |
| 4 | 2020 | Spring |
| 4 | 2019 | Summer |
| 4 | 2018 | Winter |
| 4 - 6 | 2018 | Fall |
| 9 | 2017 | Winter |
| 7 - 10 | 2017 | Fall |
| 6 - 17 | 2016 | Winter |
| 4 - 15 | 2016 | Fall |
| 5 - 12 | 2016 | Summer |
| 4 | 2016 | Spring |
| 12 - 22 | 2015 | Winter |
| 7 - 15 | 2015 | Fall |
| 7 - 45 | 2014 | Winter |
| 4 - 50 | 2014 | Fall |
| 4 | 2014 | Summer |
| 4 | 2013 | Fall |
| 10 - 17 | 2013 | Spring |
| 6 | 2012 | Winter |
| 133 | 2012 | Fall |
| 4 | 2012 | Spring |
| 4 | 2011 | Winter |
| 6 - 30 | 2011 | Fall |
| 6 | 2011 | Summer |
| 10 | 2010 | Fall |
| 4 | 2009 | Fall |
| 5 | 2009 | Spring |
| 8 | 2008 | Winter |
| 4 - 40 | 2006 | Winter |
| 4 - 30 | 2006 | Fall |
| 12 - 14 | 2005 | Winter |
| 4 - 20 | 2005 | Fall |
| 5 - 9 | 2005 | Summer |
| 20 | 2004 | Fall |
| 4 - 22 | 2003 | Fall |
| 5 | 2003 | Summer |
| 4 - 30 | 2002 | Fall |
| 10 | 2002 | Spring |
| 23 - 34 | 2001 | Winter |
| 10 - 14 | 2001 | Fall |
| 6 | 2001 | Summer |
| 4 - 12 | 2000 | Fall |
| 4 | 2000 | Summer |
| 6 | 2000 | Spring |
| 10 | 1999 | Winter |
| 6 | 1999 | Fall |
| 5 | 1999 | Summer |
| 22 | 1999 | Spring |
| 4 - 8 | 1998 | Winter |
| 5 - 18 | 1998 | Fall |
| 4 - 10 | 1998 | Summer |
| 4 - 8 | 1998 | Spring |
| 5 - 12 | 1997 | Summer |
| 5 - 10 | 1997 | Spring |
| 22 | 1996 | Fall |
| 4 - 12 | 1996 | Summer |
| 12 | 1996 | Spring |
| 5 - 10 | 1995 | Summer |
| 12 | 1995 | Spring |
| 4 - 5 | 1994 | Fall |
| 4 - 6 | 1994 | Summer |
| 6 | 1994 | Spring |
| 8 - 15 | 1993 | Summer |
| 8 - 30 | 1993 | Spring |
| 4 | 1992 | Fall |
| 5 - 18 | 1992 | Summer |
| 9 - 15 | 1992 | Spring |
| 4 | 1991 | Fall |
| 5 - 12 | 1991 | Summer |
| 6 | 1990 | Fall |
| 10 - 11 | 1990 | Summer |
| 4 | 1990 | Spring |
| Quidi Vidi Lake (NF022) | ||
|---|---|---|
| Number | Year | Season |
| 4 - 21 | 2021 | Spring |
| 4 | 2021 | Winter |
| 4 - 5 | 2019 | Winter |
| 4 - 10 | 2017 | Spring |
| 6 | 2017 | Winter |
| 4 | 2016 | Winter |
| 25 - 38 | 2015 | Spring |
| 40 - 70 | 2015 | Winter |
| 15 - 65 | 2014 | Winter |
| 5 - 45 | 2014 | Fall |
| 40 - 45 | 2014 | Spring |
| 4 - 90 | 2013 | Winter |
| 10 - 90 | 2013 | Fall |
| 8 - 19 | 2013 | Spring |
| 12 - 75 | 2012 | Winter |
| 35 - 105 | 2012 | Fall |
| 20 | 2012 | Spring |
| 10 - 70 | 2011 | Winter |
| 4 | 2011 | Summer |
| 10 - 25 | 2011 | Spring |
| 5 - 60 | 2010 | Winter |
| 10 - 57 | 2008 | Winter |
| 25 - 65 | 2006 | Spring |
| 28 | 2006 | Winter |
| 10 - 15 | 2005 | Winter |
| 20 - 40 | 2005 | Fall |
| 12 - 100 | 2004 | Winter |
| 4 | 2004 | Spring |
| 25 | 2003 | Winter |
| 85 | 2003 | Fall |
| 4 | 2002 | Winter |
| 30 - 45 | 1997 | Winter |
| 90 | 1996 | Winter |
| 65 - 75 | 1995 | Winter |
| 5 - 10 | 1993 | Fall |
| 4 - 9 | 1993 | Winter |
| 5 - 36 | 1992 | Winter |
| 4 - 23 | 1992 | Fall |
| 15 - 44 | 1991 | Winter |
| 14 - 53 | 1991 | Fall |
| 15 | 1991 | Spring |
| 35 - 79 | 1990 | Winter |
| 25 - 73 | 1990 | Fall |
| 4 - 28 | 1990 | Spring |
| Île de l'Est (QC009) | ||
|---|---|---|
| Number | Year | Season |
| 8 | 2021 | Fall |
| 11 | 2021 | Summer |
| 4 - 60 | 2019 | Fall |
| 5 - 25 | 2018 | Fall |
| 4 | 2018 | Summer |
| 6 | 2018 | Spring |
| 4 - 9 | 2016 | Fall |
| 4 - 14 | 2016 | Spring |
| 25 | 2015 | Summer |
| 5 | 2015 | Spring |
| 5 - 20 | 2014 | Summer |
| 14 - 37 | 2014 | Spring |
| 8 | 2013 | Summer |
| 8 - 20 | 2013 | Spring |
| 4 - 20 | 2011 | Summer |
| 30 | 2010 | Spring |
| 5 - 28 | 2009 | Summer |
| 6 - 30 | 2008 | Summer |
| 13 | 2008 | Spring |
| 4 - 35 | 2007 | Summer |
| 6 | 2007 | Spring |
| 6 - 25 | 2006 | Summer |
| 4 - 18 | 2005 | Summer |
| 4 - 5 | 2004 | Fall |
| 14 | 2004 | Summer |
| 5 | 2004 | Spring |
| 12 | 2003 | Fall |
| 15 | 2003 | Summer |
| 12 | 2003 | Spring |
| 19 | 2002 | Spring |
| 4 | 2001 | Fall |
| 9 | 2001 | Spring |
| 12 | 2000 | Summer |
| South Shore - East Queens Co. Sector (NS024) | ||
|---|---|---|
| Number | Year | Season |
| 30 | 2003 | Winter |
| 8 | 2001 | Winter |
| 4 | 2001 | Fall |
| 50 | 1999 | Winter |
| 4 | 1998 | Winter |
| Plages de La Martinique et de Havre-Aubert (QC005) | ||
|---|---|---|
| Number | Year | Season |
| 8 | 2021 | Summer |
| 4 - 11 | 2021 | Spring |
| 4 - 5 | 2019 | Fall |
| 7 | 2016 | Fall |
| 13 | 2016 | Summer |
| 45 | 2014 | Winter |
| 11 | 2013 | Winter |
| 5 | 2009 | Spring |
| 10 | 2008 | Spring |
| 6 | 2001 | Fall |
| 6 | 1993 | Summer |
| 4 | 1990 | Summer |
| South Shore (Port Joli sector) (NS004) | ||
|---|---|---|
| Number | Year | Season |
| 4 | 2018 | Fall |
| 13 | 2012 | Winter |
| 7 | 2007 | Winter |
| 7 | 2005 | Winter |
| 12 | 2003 | Winter |
| 32 | 2001 | Winter |
| 16 | 1999 | Winter |
| 25 | 1997 | Winter |
| 9 | 1996 | Winter |
| 10 | 1995 | Winter |
| 7 | 1994 | Winter |
| La Pointe (QC013) | ||
|---|---|---|
| Number | Year | Season |
| 6 - 31 | 2015 | Spring |
| Northern Head and South Head (NS053) | ||
|---|---|---|
| Number | Year | Season |
| 4 | 2018 | Winter |
| 4 | 2001 | Winter |
| 6 | 1999 | Winter |
| 8 - 31 | 1999 | Fall |
| 4 | 1999 | Spring |
| 4 | 1998 | Winter |
| 8 | 1996 | Winter |
| Pomquet Beach Region (NS009) | ||
|---|---|---|
| Number | Year | Season |
| 4 | 2021 | Spring |
| 13 | 2021 | Winter |
| 6 | 2019 | Fall |
| 9 | 2019 | Spring |
| 8 | 2019 | Winter |
| 4 | 2018 | Winter |
| 6 | 2013 | Fall |
| 15 | 2009 | Fall |
| 5 | 2007 | Fall |
| 23 | 2006 | Fall |
| 15 | 2000 | Winter |
| Quoddy Region (NB037) | ||
|---|---|---|
| Number | Year | Season |
| 22 | 1995 | Winter |
| Gros Morne National Park (NF045) | ||
|---|---|---|
| Number | Year | Season |
| 10 | 2012 | Winter |
| 8 | 2011 | Winter |
| 20 | 2011 | Summer |
| 5 | 2009 | Winter |
| 10 | 2008 | Summer |
| 6 | 2001 | Winter |
| 8 | 2000 | Winter |
| 9 | 1998 | Winter |
| 5 | 1991 | Winter |
| Witless Bay Islands (NF002) | ||
|---|---|---|
| Number | Year | Season |
| 20 | 2012 | Summer |
| Bassin aux Huîtres (QC015) | ||
|---|---|---|
| Number | Year | Season |
| 6 | 2016 | Spring |
| 15 | 2014 | Spring |
| Big Glace Bay Lake (NS007) | ||
|---|---|---|
| Number | Year | Season |
| 6 - 10 | 2000 | Winter |
| 12 | 1999 | Fall |
| 10 | 1999 | Winter |
| 5 - 9 | 1998 | Fall |
| Bird Islands (NS001) | ||
|---|---|---|
| Number | Year | Season |
| 10 | 2009 | Fall |
| Brier Island and Offshore Waters (NS021) | ||
|---|---|---|
| Number | Year | Season |
| 10 | 2017 | Fall |
| 5 | 2012 | Summer |
| Dune du Sud (QC024) | ||
|---|---|---|
| Number | Year | Season |
| 10 | 2019 | Fall |
| PEI National Park (PE013) | ||
|---|---|---|
| Number | Year | Season |
| 10 | 2009 | Fall |
| Île aux Loups Marins (QC027) | ||
|---|---|---|
| Number | Year | Season |
| 9 | 2018 | Spring |
| 4 | 2017 | Spring |
| 5 | 2016 | Spring |
| 4 | 2015 | Summer |
| Plage de l'Hôpital (QC012) | ||
|---|---|---|
| Number | Year | Season |
| 8 | 2014 | Summer |
| 4 | 2013 | Summer |
| Terra Nova National Park (NF017) | ||
|---|---|---|
| Number | Year | Season |
| 4 | 2002 | Winter |
| 4 | 2000 | Winter |
| 7 | 1996 | Winter |
| Cap Noir (QC016) | ||
|---|---|---|
| Number | Year | Season |
| 4 | 1997 | Summer |
| 6 | 1994 | Fall |
| Cape Freels Coastline and Cabot Island (NF025) | ||
|---|---|---|
| Number | Year | Season |
| 6 | 2011 | Fall |
| Grand Bay West to Cheeseman Prov. Pk. (NF038) | ||
|---|---|---|
| Number | Year | Season |
| 6 | 2013 | Summer |
| Île aux Goélands (QC021) | ||
|---|---|---|
| Number | Year | Season |
| 6 | 1995 | Spring |
| Quaco Bay (NB033) | ||
|---|---|---|
| Number | Year | Season |
| 6 | 2013 | Spring |
| The Brothers (NS003) | ||
|---|---|---|
| Number | Year | Season |
| 5 | 2013 | Winter |
| Bedeque Bay (PE011) | ||
|---|---|---|
| Number | Year | Season |
| 4 | 2018 | Fall |
| Cape St. Mary's (NF001) | ||
|---|---|---|
| Number | Year | Season |
| 4 | 1997 | Spring |
| The Cape Pine and St. Shotts Barren (NF015) | ||
|---|---|---|
| Number | Year | Season |
| 4 | 2015 | Summer |