In each of these lists of Chesapeake-related items, three of the things share a common characteristic that the fourth does not. Can you determine which item in each list does not belong and why?

1. dunlin, gull, sanderling, willet

2. box turtle, diamondback terrapin, painted turtle, snapping turtle

3. Patuxent, Potomac, Susquehanna, York

4. nitrogen, oxygen, phosphorus, sediment

5. DEP, DEQ, DNR, EPA

6. bufflehead, goldeneye, mallard, oldsquaw

7. copepods, dinoflagellates, rotifers, water fleas

8. nutria, Pfiesteria, purple loosestrife, rapa whelk

9. Atlantic croaker, sea bass, spot, weakfish

10. cownose ray, hogchoker, oyster toadfish, skilletfish

11. cordgrass, saltgrass, switchgrass, widgeon grass

12. Chickahominy, Conestoga, Juniata, Wiconisco

13. megalopa, spat, trochophere, veliger

14. Appalachian Province, Atlantic Coastal Plain, Chesapeake Valley, Piedmont Plateau

15. Gunpowder, Kent, Solomons, Tangier

Answers

1. The gull is the only bird in the list that is not a member of the sandpiper family. 2. The box turtle is a terrestrial turtle; the others are aquatic species. 3. The Susquehanna is a nontidal river; the others are tidal. 4. The Bay frequently lacks oxygen; it frequently has too much of the others. 5. The EPA is a federal agency charged with protecting the Bay; the others are state agencies. 6. The mallard is a dabbling duck; the others are sea ducks. 7. Dinoflagellates are phytoplankton; the others are zooplankton. 8. Pfiesteria is a harmful native species in the Bay; the others are alien harmful species. 9. The sea bass is the only fish in the group that is not a member of the drum family. 10. The cownose ray is an open water fish; the others are benthic species. 11. Widgeon grass is an underwater species; the others are marsh grasses. 12. The Chickahominy is a Virginia river; the others are Pennsylvania rivers. 13. The megalopa is an early crab stage; the others are early oyster stages. 14. The Chesapeake Valley is a nonexistent geologic province; the others are the three geologic provinces that encompass the Chesapeake watershed. 15. The Gunpowder is a river; the others are islands.