A pair of Black Oystercatchers(Haematopus bachmani)established a nest in June 2022 at“Tern Town”,an island located in Hayward,California along the eastern side of the San Francisco Bay.This is the first documented o...A pair of Black Oystercatchers(Haematopus bachmani)established a nest in June 2022 at“Tern Town”,an island located in Hayward,California along the eastern side of the San Francisco Bay.This is the first documented occurrence of oystercatchers successfully nesting and fledgling young in association with California Least Terns.The island provides nesting habitat for three special status species.Since 2015,and for a total of six breeding seasons,the endangered California Least Tern(Sternula antillarum browni),the threatened Western Snowy Plover(Charadrius alexandrinus nivosus)and species-of-special-concern Black Skimmer(Rynchops niger),have nested successfully,in association with American Avocet(Recurvirostra americana)and Black-necked Stilt(Himantopus mexicanus).We collected shells near the oystercatcher nest to assess their diet.Diet data showed the oystercatchers foraged on,in decreasing order of abundance,Japanese Little-necked Clams(Ruditapes philippinarum),Ribbed Mussels(Geukensia demissa),Bent-nose Clams(Macoma nasuta),Limpets(Patellogastropoda sp.)and Bay Mussels(Mytilus edulis).This new report on breeding Black Oystercatchers indicates that managing habitat for California Least Tern,Western Snowy Plover,and Black Skimmer can also benefit Black Oystercatcher.This site-specific information on breeding Black Oystercatchers supports recovery plan tasks that are consistent with managing habitat for California Least Tern,Western Snowy Plover and Black Skimmer.展开更多
The water treatment effect of a protein skimmer with different ozone concentrations for recirculation system of industrial fish farming was studied in this paper.Foam separation principle and ammonia nitrogen removing...The water treatment effect of a protein skimmer with different ozone concentrations for recirculation system of industrial fish farming was studied in this paper.Foam separation principle and ammonia nitrogen removing theory of the protein skimmer was described.A protein skimmer with a discharge of 50 m3·h-1 was designed.The skimmer was used in a recirculation system,and relative water quality parameters: protein,ammonia nitrogen,nitrite,nitrate,organic nitrogen,suspended solid,dissolved oxygen,were tested.The results showed that the egesta of the fish reared and the feedstuff residual could be removed efficiently.The removal efficiency of ammonia nitrogen and protein in the recirculation system was very high by entering ozone into the protein skimmer.The removal rate of protein,ammonia nitrogen,nitrite,nitrate,organic nitrogen,suspended solid were various along with the different ozone concentrations.And the dissolved oxygen was greatly increased.展开更多
文摘A pair of Black Oystercatchers(Haematopus bachmani)established a nest in June 2022 at“Tern Town”,an island located in Hayward,California along the eastern side of the San Francisco Bay.This is the first documented occurrence of oystercatchers successfully nesting and fledgling young in association with California Least Terns.The island provides nesting habitat for three special status species.Since 2015,and for a total of six breeding seasons,the endangered California Least Tern(Sternula antillarum browni),the threatened Western Snowy Plover(Charadrius alexandrinus nivosus)and species-of-special-concern Black Skimmer(Rynchops niger),have nested successfully,in association with American Avocet(Recurvirostra americana)and Black-necked Stilt(Himantopus mexicanus).We collected shells near the oystercatcher nest to assess their diet.Diet data showed the oystercatchers foraged on,in decreasing order of abundance,Japanese Little-necked Clams(Ruditapes philippinarum),Ribbed Mussels(Geukensia demissa),Bent-nose Clams(Macoma nasuta),Limpets(Patellogastropoda sp.)and Bay Mussels(Mytilus edulis).This new report on breeding Black Oystercatchers indicates that managing habitat for California Least Tern,Western Snowy Plover,and Black Skimmer can also benefit Black Oystercatcher.This site-specific information on breeding Black Oystercatchers supports recovery plan tasks that are consistent with managing habitat for California Least Tern,Western Snowy Plover and Black Skimmer.
文摘The water treatment effect of a protein skimmer with different ozone concentrations for recirculation system of industrial fish farming was studied in this paper.Foam separation principle and ammonia nitrogen removing theory of the protein skimmer was described.A protein skimmer with a discharge of 50 m3·h-1 was designed.The skimmer was used in a recirculation system,and relative water quality parameters: protein,ammonia nitrogen,nitrite,nitrate,organic nitrogen,suspended solid,dissolved oxygen,were tested.The results showed that the egesta of the fish reared and the feedstuff residual could be removed efficiently.The removal efficiency of ammonia nitrogen and protein in the recirculation system was very high by entering ozone into the protein skimmer.The removal rate of protein,ammonia nitrogen,nitrite,nitrate,organic nitrogen,suspended solid were various along with the different ozone concentrations.And the dissolved oxygen was greatly increased.
