{"id":2905,"date":"2008-05-08T12:17:30","date_gmt":"2008-05-08T16:17:30","guid":{"rendered":"https:\/\/www.sciencenews.org\/article\/risky-nests"},"modified":"2019-08-08T12:34:57","modified_gmt":"2019-08-08T16:34:57","slug":"risky-nests","status":"publish","type":"post","link":"https:\/\/www.sciencenews.org\/article\/risky-nests","title":{"rendered":"Risky nests"},"content":{"rendered":"\n<p>Out-of-control grasses may lure song sparrows near San Francisco into bad\nreal estate deals.<\/p>\n\n\n\n\n<p><figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"287\" src=\"https:\/\/i0.wp.com\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7753.jpg?resize=300%2C287&#038;ssl=1\" class=\"wp-image-2906 attachment-medium caption\" alt><figcaption><span class=\"caption wp-caption-2906\">SPARROW SUPPORT  Nests of Alameda song sparrows need dense tangles of plants for structural support and protection from predators. <\/span><span class=\"credit wp-credit-2906\">C. Nordby<\/span><\/figcaption><\/figure><\/p>\n\n\n\n\n<p><figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"281\" src=\"https:\/\/i0.wp.com\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7754.jpg?resize=300%2C281&#038;ssl=1\" class=\"wp-image-2907 attachment-medium caption\" alt><figcaption><span class=\"caption wp-caption-2907\">GRASSY INVASION  Thickets of Spartina cordgrass are taking over tidal marshes around San Francisco as an Atlantic cordgrass invades the West Coast and hybridizes to form a super-tough species. Dense stands trick birds into unwise nesting. <\/span><span class=\"credit wp-credit-2907\">C. Nordby<\/span><\/figcaption><\/figure><\/p>\n\n\n\n<p>Dense stands of an invasive kind of cordgrass spreading\nthrough marshes may look like great new territory for Alameda song sparrows to nest. But the lush neighborhoods\nbring an extra risk of nest-drowning floods, says Cully Nordby of the University of California,\nLos Angeles. <\/p>\n\n\n\n<p>The birds\u2019 already slim chance of successfully raising\nchicks drop from 15 percent to about 10 for nests in alien cordgrass, Nordby says.\n<\/p>\n\n\n<aside class=\"sn-conversion rich-text rich-text--with-sidebar\"><!-- wp:html -->\n<style>\n.email-conversion {\n  border: 1px solid #ffcccb;\n  color: white;\n  margin-top: 50px;\n  background-image: url(\"\/wp-content\/themes\/sciencenews\/client\/src\/images\/cta-module@2x.jpg\");\n  padding: 20px;\n  clear: both;\n}\n\n<\/style>\n<!-- \/wp:html -->\n\n<!-- wp:group {\"className\":\"email-conversion newsletter-signup__wrapper___sbuqh\"} -->\n<div id=\"emailConversion\" class=\"wp-block-group email-conversion newsletter-signup__wrapper___sbuqh\"><!-- wp:heading {\"textAlign\":\"center\"} -->\n<h2 class=\"wp-block-heading has-text-align-center\">Science News headlines, in your inbox<\/h2>\n<!-- \/wp:heading -->\n\n<!-- wp:spacer {\"height\":\"10px\"} -->\n<div style=\"height:10px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n<!-- \/wp:spacer -->\n\n<!-- wp:paragraph {\"align\":\"center\"} -->\n<p class=\"has-text-align-center\">Headlines and summaries of the latest&nbsp;Science News&nbsp;articles, delivered to your email inbox every Thursday.<\/p>\n<!-- \/wp:paragraph -->\n\n<!-- wp:sciencenews\/form-assembly-form {\"formControl\":\"edd3e5273d19837dcc2428d9676cbce7\",\"formId\":346,\"postType\":\"conversion\"} \/--><\/div>\n<!-- \/wp:group --><\/aside>\n\n\n<p>California\nhas listed this subspecies of song sparrow, <em>Melospiza\nmelodia pusillula, <\/em>as a species of special concern. Specialized for life\nalong the edges of tidal marshes, the Alameda\nsong sparrow lives only around San Francisco\u2019s SouthBay.<\/p>\n\n\n\n<p>Song sparrows choosing the new cordgrass suburbs lying lower\nin the marshes than their traditional homes do lose fewer nests to predators. But\nany advantage on that front disappears as floods in cordgrass wipe out about three\ntimes as many nests as in shrubbery elsewhere, Nordby and her colleagues report\nin an upcoming <em>Biological Invasions<\/em>.<\/p>\n\n\n\n<p>Flood-prone cordgrass could be a new kind of what biologists\ncall ecological traps, Nordby says. These traps come from environmental changes\nthat turn a species\u2019 normal, healthful urges into really bad ideas. <\/p>\n\n\n\n<p>The cordgrass <em>Spartina\nalterniflora<\/em> arrived from the Atlantic and\nGulf coasts during the 1970s. Before it could overrun the Pacific species, the\ntwo hybridized, and the offspring turned out to be a super cordgrass that\novergrows both parent species.<\/p>\n\n\n\n<p>Alameda\nsong sparrows need dense tangles of plants to support cup-shaped nests and hide\nthem from crows, raccoons and other predators. And the novel form of cordgrass could\nsatisfy an animal looking for cover, Nordby says. The hybrid <em>Spartina<\/em> can grow 2 meters tall, creating\na solid thicket that scientists and predators alike must wriggle or thrash\nthrough.<\/p>\n\n\n\n<p>Nordby and her colleagues monitored nests in the tidal\nmarshes to compare the fates of birds in the usual habitats with those in the\nexotic cordgrass.<\/p>\n\n\n\n\n<p>\u201cOne of the tricky parts of doing this research was trying\nnot to just blaze trails right to the nests,\u201d Nordby says. Yet the invasive\ncordgrass grows closer to the fringe of the marshes than Alameda song sparrows normally nest, and it\nfloods easily. (The Pacific cordgrass species grew near the marsh margins too,\nbut it straggled along in such a loose formation that the birds hardly ever\nmoved in.)<\/p>\n\n\n\n\n<p><br><br><\/p>\n\n\n<aside class=\"sn-conversion rich-text rich-text--with-sidebar\"><!-- wp:paragraph {\"align\":\"center\",\"style\":{\"elements\":{\"link\":{\"color\":{\"text\":\"var:preset|color|gray-mid\"}}}},\"backgroundColor\":\"gray-light\",\"textColor\":\"gray-mid\"} -->\n<p class=\"has-text-align-center has-gray-mid-color has-gray-light-background-color has-text-color has-background has-link-color\" id=\"inline2\">Science News sponsorship position.<\/p>\n<!-- \/wp:paragraph --><\/aside>\n\nBuilding a nest and starting a family takes at least a\nmonth, Nordby says, so a new home can look great at first. As a full moon\napproaches and the tides peak higher and breeding season progresses, a once-dry\nnest turns into a death trap. In 2003, for example, the highest tide of the\nmonth rose from 1.89 meters in March to 2.13 meters in July.\n\n\n<p>\u201cI\u2019ve seen eggs floating,\u201d Nordby says. If they manage to\nsettle back down into the nest, parents can take up incubating them again. If\nthe eggs wash overboard, though, they\u2019re doomed.<span> <\/span>\u201cEven a matter of half an inch can make a\ndifference,\u201d Nordby says.<\/p>\n\n\n\n<p>The grass looks like a problem, says Martin Schlaepfer of\nthe State University of New York College of Environmental Science and Forestry\nin Syracuse. He\nsays, though, that he\u2019d like to learn more about the preferences of the birds\nfor the new cordgrass versus the familiar nesting sites. In the strictest\ndefinition, a trap lures animals away from the old grounds instead of just\nproviding an imperfect habitat. <\/p>\n","protected":false},"excerpt":{"rendered":"<p>Invasive species misleads birds picking a home.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"deck":"Invader grass tricks song sparrows","article_citations":"<br \/>Nordby, J.C., A.N. Cohen, and S.R. Beissinger . In press. Effects of a habitat-altering invader on nesting sparrows: An ecological trap? Biological Invasions.","styled-title":"","footnotes":""},"categories":[1],"tags":[],"topic":[936,927],"article-type":[93],"editors-picks":[],"sn-connection":[],"story-type":[],"coauthors":[{"display_name":"Susan Milius","user_nicename":"susan-milius"}],"class_list":["post-2905","post","type-post","status-publish","format-standard","hentry","category-uncategorized","topic-life","topic-earth","article-type-news"],"has_blocks":true,"block_data":[{"blockName":"core\/paragraph","attrs":{"align":"","content":"Out-of-control grasses may lure song sparrows near San Francisco into bad\nreal estate deals.","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>Out-of-control grasses may lure song sparrows near San Francisco into bad\nreal estate deals.<\/p>\n\n","innerContent":["\n<p>Out-of-control grasses may lure song sparrows near San Francisco into bad\nreal estate deals.<\/p>\n\n"],"rendered":"\n<p>Out-of-control grasses may lure song sparrows near San Francisco into bad\nreal estate deals.<\/p>\n\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"<figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img width=\"300\" height=\"287\" src=\"https:\/\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7753.jpg\" class=\"wp-image-2906 attachment-medium caption\" alt \/><figcaption>SPARROW SUPPORT  Nests of Alameda song sparrows need dense tangles of plants for structural support and protection from predators. <\/figcaption><\/figure>","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p><figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img width=\"300\" height=\"287\" src=\"https:\/\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7753.jpg\" class=\"wp-image-2906 attachment-medium caption\" alt><figcaption>SPARROW SUPPORT  Nests of Alameda song sparrows need dense tangles of plants for structural support and protection from predators. <\/figcaption><\/figure><\/p>\n\n","innerContent":["\n<p><figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img width=\"300\" height=\"287\" src=\"https:\/\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7753.jpg\" class=\"wp-image-2906 attachment-medium caption\" alt><figcaption>SPARROW SUPPORT  Nests of Alameda song sparrows need dense tangles of plants for structural support and protection from predators. <\/figcaption><\/figure><\/p>\n\n"],"rendered":"\n<p><figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img width=\"300\" height=\"287\" src=\"https:\/\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7753.jpg\" class=\"wp-image-2906 attachment-medium caption\" alt><figcaption>SPARROW SUPPORT  Nests of Alameda song sparrows need dense tangles of plants for structural support and protection from predators. <\/figcaption><\/figure><\/p>\n\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"<figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img width=\"300\" height=\"281\" src=\"https:\/\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7754.jpg\" class=\"wp-image-2907 attachment-medium caption\" alt \/><figcaption>GRASSY INVASION  Thickets of Spartina cordgrass are taking over tidal marshes around San Francisco as an Atlantic cordgrass invades the West Coast and hybridizes to form a super-tough species. Dense stands trick birds into unwise nesting. <\/figcaption><\/figure>","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p><figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img width=\"300\" height=\"281\" src=\"https:\/\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7754.jpg\" class=\"wp-image-2907 attachment-medium caption\" alt><figcaption>GRASSY INVASION  Thickets of Spartina cordgrass are taking over tidal marshes around San Francisco as an Atlantic cordgrass invades the West Coast and hybridizes to form a super-tough species. Dense stands trick birds into unwise nesting. <\/figcaption><\/figure><\/p>\n","innerContent":["\n<p><figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img width=\"300\" height=\"281\" src=\"https:\/\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7754.jpg\" class=\"wp-image-2907 attachment-medium caption\" alt><figcaption>GRASSY INVASION  Thickets of Spartina cordgrass are taking over tidal marshes around San Francisco as an Atlantic cordgrass invades the West Coast and hybridizes to form a super-tough species. Dense stands trick birds into unwise nesting. <\/figcaption><\/figure><\/p>\n"],"rendered":"\n<p><figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img width=\"300\" height=\"281\" src=\"https:\/\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7754.jpg\" class=\"wp-image-2907 attachment-medium caption\" alt><figcaption>GRASSY INVASION  Thickets of Spartina cordgrass are taking over tidal marshes around San Francisco as an Atlantic cordgrass invades the West Coast and hybridizes to form a super-tough species. Dense stands trick birds into unwise nesting. <\/figcaption><\/figure><\/p>\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"Dense stands of an invasive kind of cordgrass spreading\nthrough marshes may look like great new territory for Alameda song sparrows to nest. But the lush neighborhoods\nbring an extra risk of nest-drowning floods, says Cully Nordby of the University of California,\nLos Angeles. ","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>Dense stands of an invasive kind of cordgrass spreading\nthrough marshes may look like great new territory for Alameda song sparrows to nest. But the lush neighborhoods\nbring an extra risk of nest-drowning floods, says Cully Nordby of the University of California,\nLos Angeles. <\/p>\n","innerContent":["\n<p>Dense stands of an invasive kind of cordgrass spreading\nthrough marshes may look like great new territory for Alameda song sparrows to nest. But the lush neighborhoods\nbring an extra risk of nest-drowning floods, says Cully Nordby of the University of California,\nLos Angeles. <\/p>\n"],"rendered":"\n<p>Dense stands of an invasive kind of cordgrass spreading\nthrough marshes may look like great new territory for Alameda song sparrows to nest. But the lush neighborhoods\nbring an extra risk of nest-drowning floods, says Cully Nordby of the University of California,\nLos Angeles. <\/p>\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"The birds\u2019 already slim chance of successfully raising\nchicks drop from 15 percent to about 10 for nests in alien cordgrass, Nordby says.\n","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>The birds\u2019 already slim chance of successfully raising\nchicks drop from 15 percent to about 10 for nests in alien cordgrass, Nordby says.\n<\/p>\n","innerContent":["\n<p>The birds\u2019 already slim chance of successfully raising\nchicks drop from 15 percent to about 10 for nests in alien cordgrass, Nordby says.\n<\/p>\n"],"rendered":"\n<p>The birds\u2019 already slim chance of successfully raising\nchicks drop from 15 percent to about 10 for nests in alien cordgrass, Nordby says.\n<\/p>\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"California\nhas listed this subspecies of song sparrow, <em>Melospiza\nmelodia pusillula, <\/em>as a species of special concern. Specialized for life\nalong the edges of tidal marshes, the Alameda\nsong sparrow lives only around San Francisco\u2019s SouthBay.","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>California\nhas listed this subspecies of song sparrow, <em>Melospiza\nmelodia pusillula, <\/em>as a species of special concern. Specialized for life\nalong the edges of tidal marshes, the Alameda\nsong sparrow lives only around San Francisco\u2019s SouthBay.<\/p>\n","innerContent":["\n<p>California\nhas listed this subspecies of song sparrow, <em>Melospiza\nmelodia pusillula, <\/em>as a species of special concern. Specialized for life\nalong the edges of tidal marshes, the Alameda\nsong sparrow lives only around San Francisco\u2019s SouthBay.<\/p>\n"],"rendered":"\n<p>California\nhas listed this subspecies of song sparrow, <em>Melospiza\nmelodia pusillula, <\/em>as a species of special concern. Specialized for life\nalong the edges of tidal marshes, the Alameda\nsong sparrow lives only around San Francisco\u2019s SouthBay.<\/p>\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"Song sparrows choosing the new cordgrass suburbs lying lower\nin the marshes than their traditional homes do lose fewer nests to predators. But\nany advantage on that front disappears as floods in cordgrass wipe out about three\ntimes as many nests as in shrubbery elsewhere, Nordby and her colleagues report\nin an upcoming <em>Biological Invasions<\/em>.","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>Song sparrows choosing the new cordgrass suburbs lying lower\nin the marshes than their traditional homes do lose fewer nests to predators. But\nany advantage on that front disappears as floods in cordgrass wipe out about three\ntimes as many nests as in shrubbery elsewhere, Nordby and her colleagues report\nin an upcoming <em>Biological Invasions<\/em>.<\/p>\n","innerContent":["\n<p>Song sparrows choosing the new cordgrass suburbs lying lower\nin the marshes than their traditional homes do lose fewer nests to predators. But\nany advantage on that front disappears as floods in cordgrass wipe out about three\ntimes as many nests as in shrubbery elsewhere, Nordby and her colleagues report\nin an upcoming <em>Biological Invasions<\/em>.<\/p>\n"],"rendered":"\n<p>Song sparrows choosing the new cordgrass suburbs lying lower\nin the marshes than their traditional homes do lose fewer nests to predators. But\nany advantage on that front disappears as floods in cordgrass wipe out about three\ntimes as many nests as in shrubbery elsewhere, Nordby and her colleagues report\nin an upcoming <em>Biological Invasions<\/em>.<\/p>\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"Flood-prone cordgrass could be a new kind of what biologists\ncall ecological traps, Nordby says. These traps come from environmental changes\nthat turn a species\u2019 normal, healthful urges into really bad ideas. ","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>Flood-prone cordgrass could be a new kind of what biologists\ncall ecological traps, Nordby says. These traps come from environmental changes\nthat turn a species\u2019 normal, healthful urges into really bad ideas. <\/p>\n","innerContent":["\n<p>Flood-prone cordgrass could be a new kind of what biologists\ncall ecological traps, Nordby says. These traps come from environmental changes\nthat turn a species\u2019 normal, healthful urges into really bad ideas. <\/p>\n"],"rendered":"\n<p>Flood-prone cordgrass could be a new kind of what biologists\ncall ecological traps, Nordby says. These traps come from environmental changes\nthat turn a species\u2019 normal, healthful urges into really bad ideas. <\/p>\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"The cordgrass <em>Spartina\nalterniflora<\/em> arrived from the Atlantic and\nGulf coasts during the 1970s. Before it could overrun the Pacific species, the\ntwo hybridized, and the offspring turned out to be a super cordgrass that\novergrows both parent species.","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>The cordgrass <em>Spartina\nalterniflora<\/em> arrived from the Atlantic and\nGulf coasts during the 1970s. Before it could overrun the Pacific species, the\ntwo hybridized, and the offspring turned out to be a super cordgrass that\novergrows both parent species.<\/p>\n","innerContent":["\n<p>The cordgrass <em>Spartina\nalterniflora<\/em> arrived from the Atlantic and\nGulf coasts during the 1970s. Before it could overrun the Pacific species, the\ntwo hybridized, and the offspring turned out to be a super cordgrass that\novergrows both parent species.<\/p>\n"],"rendered":"\n<p>The cordgrass <em>Spartina\nalterniflora<\/em> arrived from the Atlantic and\nGulf coasts during the 1970s. Before it could overrun the Pacific species, the\ntwo hybridized, and the offspring turned out to be a super cordgrass that\novergrows both parent species.<\/p>\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"Alameda\nsong sparrows need dense tangles of plants to support cup-shaped nests and hide\nthem from crows, raccoons and other predators. And the novel form of cordgrass could\nsatisfy an animal looking for cover, Nordby says. The hybrid <em>Spartina<\/em> can grow 2 meters tall, creating\na solid thicket that scientists and predators alike must wriggle or thrash\nthrough.","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>Alameda\nsong sparrows need dense tangles of plants to support cup-shaped nests and hide\nthem from crows, raccoons and other predators. And the novel form of cordgrass could\nsatisfy an animal looking for cover, Nordby says. The hybrid <em>Spartina<\/em> can grow 2 meters tall, creating\na solid thicket that scientists and predators alike must wriggle or thrash\nthrough.<\/p>\n","innerContent":["\n<p>Alameda\nsong sparrows need dense tangles of plants to support cup-shaped nests and hide\nthem from crows, raccoons and other predators. And the novel form of cordgrass could\nsatisfy an animal looking for cover, Nordby says. The hybrid <em>Spartina<\/em> can grow 2 meters tall, creating\na solid thicket that scientists and predators alike must wriggle or thrash\nthrough.<\/p>\n"],"rendered":"\n<p>Alameda\nsong sparrows need dense tangles of plants to support cup-shaped nests and hide\nthem from crows, raccoons and other predators. And the novel form of cordgrass could\nsatisfy an animal looking for cover, Nordby says. The hybrid <em>Spartina<\/em> can grow 2 meters tall, creating\na solid thicket that scientists and predators alike must wriggle or thrash\nthrough.<\/p>\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"Nordby and her colleagues monitored nests in the tidal\nmarshes to compare the fates of birds in the usual habitats with those in the\nexotic cordgrass.","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>Nordby and her colleagues monitored nests in the tidal\nmarshes to compare the fates of birds in the usual habitats with those in the\nexotic cordgrass.<\/p>\n\n","innerContent":["\n<p>Nordby and her colleagues monitored nests in the tidal\nmarshes to compare the fates of birds in the usual habitats with those in the\nexotic cordgrass.<\/p>\n\n"],"rendered":"\n<p>Nordby and her colleagues monitored nests in the tidal\nmarshes to compare the fates of birds in the usual habitats with those in the\nexotic cordgrass.<\/p>\n\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"\u201cOne of the tricky parts of doing this research was trying\nnot to just blaze trails right to the nests,\u201d Nordby says. Yet the invasive\ncordgrass grows closer to the fringe of the marshes than Alameda song sparrows normally nest, and it\nfloods easily. (The Pacific cordgrass species grew near the marsh margins too,\nbut it straggled along in such a loose formation that the birds hardly ever\nmoved in.)","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>\u201cOne of the tricky parts of doing this research was trying\nnot to just blaze trails right to the nests,\u201d Nordby says. Yet the invasive\ncordgrass grows closer to the fringe of the marshes than Alameda song sparrows normally nest, and it\nfloods easily. (The Pacific cordgrass species grew near the marsh margins too,\nbut it straggled along in such a loose formation that the birds hardly ever\nmoved in.)<\/p>\n\n","innerContent":["\n<p>\u201cOne of the tricky parts of doing this research was trying\nnot to just blaze trails right to the nests,\u201d Nordby says. Yet the invasive\ncordgrass grows closer to the fringe of the marshes than Alameda song sparrows normally nest, and it\nfloods easily. (The Pacific cordgrass species grew near the marsh margins too,\nbut it straggled along in such a loose formation that the birds hardly ever\nmoved in.)<\/p>\n\n"],"rendered":"\n<p>\u201cOne of the tricky parts of doing this research was trying\nnot to just blaze trails right to the nests,\u201d Nordby says. Yet the invasive\ncordgrass grows closer to the fringe of the marshes than Alameda song sparrows normally nest, and it\nfloods easily. (The Pacific cordgrass species grew near the marsh margins too,\nbut it straggled along in such a loose formation that the birds hardly ever\nmoved in.)<\/p>\n\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"<br \/><br \/>","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p><br><br><\/p>\n","innerContent":["\n<p><br><br><\/p>\n"],"rendered":"\n<p><br><br><\/p>\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"\u201cI\u2019ve seen eggs floating,\u201d Nordby says. If they manage to\nsettle back down into the nest, parents can take up incubating them again. If\nthe eggs wash overboard, though, they\u2019re doomed.<span> <\/span>\u201cEven a matter of half an inch can make a\ndifference,\u201d Nordby says.","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>\u201cI\u2019ve seen eggs floating,\u201d Nordby says. If they manage to\nsettle back down into the nest, parents can take up incubating them again. If\nthe eggs wash overboard, though, they\u2019re doomed.<span> <\/span>\u201cEven a matter of half an inch can make a\ndifference,\u201d Nordby says.<\/p>\n","innerContent":["\n<p>\u201cI\u2019ve seen eggs floating,\u201d Nordby says. If they manage to\nsettle back down into the nest, parents can take up incubating them again. If\nthe eggs wash overboard, though, they\u2019re doomed.<span> <\/span>\u201cEven a matter of half an inch can make a\ndifference,\u201d Nordby says.<\/p>\n"],"rendered":"\n<p>\u201cI\u2019ve seen eggs floating,\u201d Nordby says. If they manage to\nsettle back down into the nest, parents can take up incubating them again. If\nthe eggs wash overboard, though, they\u2019re doomed.<span> <\/span>\u201cEven a matter of half an inch can make a\ndifference,\u201d Nordby says.<\/p>\n"},{"blockName":"core\/paragraph","attrs":{"align":"","content":"The grass looks like a problem, says Martin Schlaepfer of\nthe State University of New York College of Environmental Science and Forestry\nin Syracuse. He\nsays, though, that he\u2019d like to learn more about the preferences of the birds\nfor the new cordgrass versus the familiar nesting sites. In the strictest\ndefinition, a trap lures animals away from the old grounds instead of just\nproviding an imperfect habitat. ","dropCap":false,"placeholder":"","direction":"","lock":[],"metadata":[],"className":"","style":[],"backgroundColor":"","textColor":"","gradient":"","fontSize":"","fontFamily":"","borderColor":"","anchor":""},"innerBlocks":[],"innerHTML":"\n<p>The grass looks like a problem, says Martin Schlaepfer of\nthe State University of New York College of Environmental Science and Forestry\nin Syracuse. He\nsays, though, that he\u2019d like to learn more about the preferences of the birds\nfor the new cordgrass versus the familiar nesting sites. In the strictest\ndefinition, a trap lures animals away from the old grounds instead of just\nproviding an imperfect habitat. <\/p>\n","innerContent":["\n<p>The grass looks like a problem, says Martin Schlaepfer of\nthe State University of New York College of Environmental Science and Forestry\nin Syracuse. He\nsays, though, that he\u2019d like to learn more about the preferences of the birds\nfor the new cordgrass versus the familiar nesting sites. In the strictest\ndefinition, a trap lures animals away from the old grounds instead of just\nproviding an imperfect habitat. <\/p>\n"],"rendered":"\n<p>The grass looks like a problem, says Martin Schlaepfer of\nthe State University of New York College of Environmental Science and Forestry\nin Syracuse. He\nsays, though, that he\u2019d like to learn more about the preferences of the birds\nfor the new cordgrass versus the familiar nesting sites. In the strictest\ndefinition, a trap lures animals away from the old grounds instead of just\nproviding an imperfect habitat. <\/p>\n"}],"jetpack_featured_media_url":"","sn_app_content":"<p>Out-of-control grasses may lure song sparrows near San Francisco into bad\nreal estate deals.<\/p>\n\n\n\n\n<p><figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"287\" src=\"https:\/\/i0.wp.com\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7753.jpg?resize=300%2C287&#038;ssl=1\" class=\"wp-image-2906 attachment-medium caption\" alt><figcaption><span class=\"caption wp-caption-2906\">SPARROW SUPPORT  Nests of Alameda song sparrows need dense tangles of plants for structural support and protection from predators. <\/span><span class=\"credit wp-credit-2906\">C. Nordby<\/span><\/figcaption><\/figure><\/p>\n\n\n\n\n<p><figure class=\"wp-block-image\" style=\"width: 300px; float: right;\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"281\" src=\"https:\/\/i0.wp.com\/www.sciencenews.org\/wp-content\/uploads\/2008\/05\/7754.jpg?resize=300%2C281&#038;ssl=1\" class=\"wp-image-2907 attachment-medium caption\" alt><figcaption><span class=\"caption wp-caption-2907\">GRASSY INVASION  Thickets of Spartina cordgrass are taking over tidal marshes around San Francisco as an Atlantic cordgrass invades the West Coast and hybridizes to form a super-tough species. Dense stands trick birds into unwise nesting. <\/span><span class=\"credit wp-credit-2907\">C. Nordby<\/span><\/figcaption><\/figure><\/p>\n\n\n\n\n\n\n\n\n\n<p>Dense stands of an invasive kind of cordgrass spreading\nthrough marshes may look like great new territory for Alameda song sparrows to nest. But the lush neighborhoods\nbring an extra risk of nest-drowning floods, says Cully Nordby of the University of California,\nLos Angeles. <\/p>\n\n\n\n\n\n\n\n\n\n<p>The birds\u2019 already slim chance of successfully raising\nchicks drop from 15 percent to about 10 for nests in alien cordgrass, Nordby says.\n<\/p>\n\n\n\n\n\n\n\n\n\n<p>California\nhas listed this subspecies of song sparrow, <em>Melospiza\nmelodia pusillula, <\/em>as a species of special concern. Specialized for life\nalong the edges of tidal marshes, the Alameda\nsong sparrow lives only around San Francisco\u2019s SouthBay.<\/p>\n\n\n\n\n\n\n\n\n\n<p>Song sparrows choosing the new cordgrass suburbs lying lower\nin the marshes than their traditional homes do lose fewer nests to predators. But\nany advantage on that front disappears as floods in cordgrass wipe out about three\ntimes as many nests as in shrubbery elsewhere, Nordby and her colleagues report\nin an upcoming <em>Biological Invasions<\/em>.<\/p>\n\n\n\n\n\n\n\n\n\n<p>Flood-prone cordgrass could be a new kind of what biologists\ncall ecological traps, Nordby says. These traps come from environmental changes\nthat turn a species\u2019 normal, healthful urges into really bad ideas. <\/p>\n\n\n\n\n\n\n\n\n\n<p>The cordgrass <em>Spartina\nalterniflora<\/em> arrived from the Atlantic and\nGulf coasts during the 1970s. Before it could overrun the Pacific species, the\ntwo hybridized, and the offspring turned out to be a super cordgrass that\novergrows both parent species.<\/p>\n\n\n\n\n\n\n\n\n\n<p>Alameda\nsong sparrows need dense tangles of plants to support cup-shaped nests and hide\nthem from crows, raccoons and other predators. And the novel form of cordgrass could\nsatisfy an animal looking for cover, Nordby says. The hybrid <em>Spartina<\/em> can grow 2 meters tall, creating\na solid thicket that scientists and predators alike must wriggle or thrash\nthrough.<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n<p>Nordby and her colleagues monitored nests in the tidal\nmarshes to compare the fates of birds in the usual habitats with those in the\nexotic cordgrass.<\/p>\n\n\n\n\n<p>\u201cOne of the tricky parts of doing this research was trying\nnot to just blaze trails right to the nests,\u201d Nordby says. Yet the invasive\ncordgrass grows closer to the fringe of the marshes than Alameda song sparrows normally nest, and it\nfloods easily. (The Pacific cordgrass species grew near the marsh margins too,\nbut it straggled along in such a loose formation that the birds hardly ever\nmoved in.)<\/p>\n\n\n\n\n<p><br><br><\/p>\n\n\nBuilding a nest and starting a family takes at least a\nmonth, Nordby says, so a new home can look great at first. As a full moon\napproaches and the tides peak higher and breeding season progresses, a once-dry\nnest turns into a death trap. In 2003, for example, the highest tide of the\nmonth rose from 1.89 meters in March to 2.13 meters in July.\n\n\n\n\n\n\n<p>\u201cI\u2019ve seen eggs floating,\u201d Nordby says. If they manage to\nsettle back down into the nest, parents can take up incubating them again. If\nthe eggs wash overboard, though, they\u2019re doomed.<span> <\/span>\u201cEven a matter of half an inch can make a\ndifference,\u201d Nordby says.<\/p>\n\n\n\n\n\n\n\n\n\n<p>The grass looks like a problem, says Martin Schlaepfer of\nthe State University of New York College of Environmental Science and Forestry\nin Syracuse. He\nsays, though, that he\u2019d like to learn more about the preferences of the birds\nfor the new cordgrass versus the familiar nesting sites. In the strictest\ndefinition, a trap lures animals away from the old grounds instead of just\nproviding an imperfect habitat. <\/p>","sn_mobile_render_webview":false,"sn_featured_video":null,"jetpack-related-posts":[],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/posts\/2905","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/comments?post=2905"}],"version-history":[{"count":0,"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/posts\/2905\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/media?parent=2905"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/categories?post=2905"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/tags?post=2905"},{"taxonomy":"topic","embeddable":true,"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/topic?post=2905"},{"taxonomy":"article-type","embeddable":true,"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/article-type?post=2905"},{"taxonomy":"editors-picks","embeddable":true,"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/editors-picks?post=2905"},{"taxonomy":"sn-connection","embeddable":true,"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/sn-connection?post=2905"},{"taxonomy":"story-type","embeddable":true,"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/story-type?post=2905"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/www.sciencenews.org\/wp-json\/wp\/v2\/coauthors?post=2905"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}