Related by context. Frequent words. (Click for all words.) 75 algae blooms 71 algal blooms 70 algal bloom 70 toxic algae 66 algae bloom 63 oxygen depletion 59 algae 59 aquatic ecosystems 58 polluted runoff 57 aquatic organisms 57 shellfish beds 56 eutrophication 56 nutrient pollution 56 dissolved oxygen 55 domoic acid 55 fecal bacteria 55 Zebra mussels 55 aquatic vegetation 55 sewer overflows 55 coral bleaching 54 sewage overflows 54 sewage spills 54 lakes 54 acidification 54 salinity 53 estuaries 53 fecal coliform 53 saltwater intrusion 53 waterways 53 fecal coliform bacteria 53 eelgrass 52 aquatic species 52 shellfish harvesting 52 siltation 52 turbidity 52 cyanobacteria 52 zebra mussels 52 sedimentation 51 coastal waters 51 alga 51 sediment 51 freshwater lakes 51 fecal contamination 50 aquatic habitat 50 mercury contamination 50 hydrilla 50 silting 50 respiratory irritation 50 pollution 50 oyster reefs 50 hypoxia 50 microscopic organisms 50 sewage overflow 50 lake 50 invasive species 49 Invasive species 49 E. coli bacteria 49 estuarine 49 milfoil 49 reefs 49 estuary 49 Overfishing 49 marine ecosystems 49 quagga mussels 49 ocean ecosystems 49 gizzard shad 49 mass extinctions 49 soil erosion 49 rivers 49 sea lice 49 zebra mussel 49 overfishing 48 wastewater discharges 48 Melting snow 48 aquatic insects 48 Rip currents 48 stormwater pollution 48 overharvesting 48 otters 48 copepods 48 marine organisms 48 bacterial contamination 48 arsenic contamination 48 endocrine disruptors 48 freshwater 47 manatees 47 bacteria 47 insect populations 47 phytoplankton 47 pollutants 47 contaminants 47 coastal ecosystems 47 glacial lakes 47 shorelines 47 Polluted 47 toxins 47 plankton 47 dieback 47 ponds 47 aquatic invasive species 47 marsh grasses