{"id":6956,"date":"2020-03-17T17:35:05","date_gmt":"2020-03-17T21:35:05","guid":{"rendered":"http:\/\/pibo.ca\/en\/?page_id=6956"},"modified":"2022-03-25T12:39:19","modified_gmt":"2022-03-25T16:39:19","slug":"barn-swallow","status":"publish","type":"page","link":"https:\/\/pibo.ca\/en\/research\/species-at-risk\/barn-swallow\/","title":{"rendered":"Barn Swallow: A Report"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"6956\" class=\"elementor elementor-6956\" data-elementor-post-type=\"page\">\n\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-2b89b11 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"2b89b11\" data-element_type=\"section\" data-e-type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-99d9d8b\" data-id=\"99d9d8b\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-48907f6 elementor-widget elementor-widget-heading\" data-id=\"48907f6\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Barn Swallow: A Report<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-5ecd93e3 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"5ecd93e3\" data-element_type=\"section\" data-e-type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-367dbc5c\" data-id=\"367dbc5c\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-5861dc2c elementor-widget elementor-widget-text-editor\" data-id=\"5861dc2c\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<h3><span style=\"color: #000000;\">Purpose of this writing<\/span><\/h3><p><span style=\"color: #000000;\">We have heard that Barn Swallows are on the list of Species at Risk. In many areas they are still quite common, and it is often difficult to recognize that their population is in decline. I wrote this essay to explain why they are listed as \u201cthreatened\u201d and to inform interested non-researchers about their declining population.<\/span><\/p><p><span style=\"color: #000000;\">&#8211; Sumiko Onishi, Field Supervisor\/Bander in Charge<\/span><\/p><h2><span style=\"color: #000000;\">The Population Trend &#8211; Let\u2019s watch the Barn Swallow!<\/span><\/h2><p><span style=\"color: #000000;\">In April of each year migratory swallows start showing up on Pelee Island and we feel the change of seasons as soon as we see them.\u00a0 Barn Swallows, and their closely related cousins, Purple Martins are lined up on hydro lines beside the roadside making lively chattering noises whenever we see them. They are like familiar neighbors that have come back from their annual trip.<\/span><\/p><p><span style=\"color: #000000;\">Barn Swallows (Hirundo rustica) are common swallow species seen the world over. They live on every continent except Antarctica. Because the population is widespread, they are listed as a \u2018least concern\u2019 species which does not require special protection by the International Union for Conservation of Nature and Natural Resources.<\/span><\/p><p><span style=\"color: #000000;\">A nature essay written in the 1980s in my home country of Japan described how Hirundo rustica used to nest under the eaves and the walls of every house in the early 1900s. Some of the house owners built ramps under their nests to support their fledglings which also help avoiding the birds\u2019 feces landing on the floor. The owners often created openings to allow the swallows to enter and exit the house. With the advent of modern agriculture in the 1950s, farmlands were sprayed with pesticides where hundreds of Barn Swallows flying all around to feed on the disturbed insects. \u00a0The author points out that far fewer swallows have been seen after those changes in agriculture took place.\u00a0\u00a0 Since the early 2000s some districts in Japan have started listing Hirundo rustica as a species at risk. Of course, there are other reasons for population decline, such as habitat loss. European scientists have pointed out that Hirundo rustica\u2019s population has declined by almost fifty percent since 1975.\u00a0 It is also clear that their population has been significantly affected by changing land use patterns.<\/span><\/p><p><span style=\"color: #000000;\">On Pelee Island we see large groups of Barn Swallows after their arrival roosting in the tall grasses around Lake Henry and Fox Pond during their breeding season. They are very busy collecting dry grasses and mud from the unpaved roads and ditches to build their nests and raise their fledglings. They build many of their homes around our houses and we are entertained by them throughout the summer. It is sometimes hard to imagine that their population is actually declining.<\/span><\/p><p><span style=\"color: #000000;\">In Canada the population decline has been observed since the mid-1980s. The Breeding Bird Survey conducted by Environment and Climate Change Canada&#8217;s Canadian Wildlife Service, showed a population decline of 3.6% per year, which translates into a total population decrease of 76% for the past 40 years. As a result of these findings, Barn Swallows were listed in 2011 as \u2018Threatened\u2019 by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), which serves as an independent advisor to the Minister of Environment and Climate Change Canada. Based on 30% decline of the population in the last ten years of this study the Ontario government has become concerned that they are very likely to become endangered. The Ontario Species at Risk Act in 2012 listed the Barn Swallow as \u201cthreatened\u201d.<\/span><\/p><p><span style=\"color: #000000;\">Recently we received an organized summary of some of the data we collected for the years 2003 to 2016 which were produced by the Canadian Migration Monitoring Network (CMMN). According to the summary, our annual survey indicates that the spring Barn Swallow population on Pelee Island has declined by 4.11% a year for the 14 years. This decline in our data is still not as significant as that seen in other CMMN stations in Ontario and Quebec.<\/span><\/p><p><span style=\"color: #000000;\">In Canada, Bird Canada, (former Bird Study Canada) has made a serious effort to grapple with this decline. They are experimenting with special nest boxes for the species to learn about behavior and habitat.\u00a0 This population decline is getting attention all over the world. Behavior like breeding near a manmade environment, and the pattern of gathering closely together for nesting might have a big effect on their population trend. Studies in Europe (Denmark) published in 2001 observed that clutch sizes are affected by the availability of their food, which mainly consists of insects associated with cattle. Decreasing of the number of young successfully fledged results in smaller populations returning to the area over the years.<\/span><\/p><p><span style=\"color: #000000;\">We are interested in seeing the long-term trends of the Barn Swallow population at our station, and if our results are different from those of other CMMN stations. Also, we hope our unique location will provide a happy home for the breeding and roosting population, and they will flourish on Pelee Island.<\/span><\/p><p><span style=\"color: #000000;\">To those who are more interested in other species population trends please visit Bird Canada\u2019s NatureCounts website. Thank you for CMMN to provide those data for us.<\/span><\/p><h3><span style=\"color: #000000;\">Sources<\/span><\/h3><p><span style=\"color: #000000;\">NatureCounts, Birds Canada<\/span><\/p><p><span style=\"color: #000000;\">https:\/\/www.birdscanada.org\/birdmon\/default\/main.jsp<\/span><\/p><p><span style=\"color: #000000;\">Liam Casey, \u201cInside Ontario\u2019s fight to save declining barn swallows, one bird house at a time\u201d, The Canadian Press 2017<\/span><\/p><p><blockquote class=\"wp-embedded-content\" data-secret=\"K6uJBxMEgj\"><a href=\"https:\/\/globalnews.ca\/news\/3574472\/inside-ontarios-fight-to-save-declining-barn-swallows-one-bird-house-at-a-time\/\">Inside Ontario&#8217;s fight to save declining barn swallows, one bird house at a time<\/a><\/blockquote><iframe class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; clip: rect(1px, 1px, 1px, 1px);\" title=\"&#8220;Inside Ontario&#8217;s fight to save declining barn swallows, one bird house at a time&#8221; &#8212; Global News\" src=\"https:\/\/globalnews.ca\/news\/3574472\/inside-ontarios-fight-to-save-declining-barn-swallows-one-bird-house-at-a-time\/embed\/#?secret=RNSRfPYRdM#?secret=K6uJBxMEgj\" data-secret=\"K6uJBxMEgj\" width=\"500\" height=\"282\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe><\/p><p><span style=\"color: #000000;\">Species at Risk, Government of Canada<\/span><\/p><p><span style=\"color: #000000;\">https:\/\/www.canada.ca\/en\/environment-climate-change\/services\/species-risk-public-registry\/cosewic-assessments-status-reports\/barn-swallow-2011.html#_cas<\/span><\/p><p><span style=\"color: #000000;\">Muku Hatojyu, Historia Naturalis (1984)<\/span><\/p><p><span style=\"color: #000000;\">Peter, D. Moore, Dairy declines hard to swallow, Nature (21 June 2001)<\/span><\/p><p><span style=\"color: #000000;\">https:\/\/www.nature.com\/articles\/35082185<\/span><\/p><p><span style=\"color: #000000;\">M\u00f8ller, A. P. J. Appl. Ecol. 38, 378\u2013389 (2001)<\/span><\/p><h6>Photos of Barn Swallows by Sumiko Onishi<\/h6><p><span style=\"color: #000000;\"><strong>Key to the output files<\/strong><\/span><br \/><span style=\"color: #000000;\">\u2022 Trend file:<\/span><br \/><span style=\"color: #000000;\">o \u201cTrnd\u201d is the estimate of % change per year over the period analyzed.<\/span><br \/><span style=\"color: #000000;\">o \u201cpost_prob\u201d indicates the posterior probability that the direction of the trend (positive or negative) is <\/span><span style=\"color: #000000;\">correct. This number can be used as a pseudo p-value, such that trends with a posterior probability &gt;<\/span> <span style=\"color: #000000;\">0.9 can be considered to have strong support.<\/span><br \/><span style=\"color: #000000;\">o \u201clower_ci\u201d and \u201cupper_ci\u201d (lower and upper credible interval) define the range of values within which <\/span><span style=\"color: #000000;\">the true trend or annual index falls with a probability of 95%.<\/span><br \/><span style=\"color: #000000;\">o \u201canalysis_code\u201d indicates the temporal pattern of presence for each species at each site. Table 1 <\/span><span style=\"color: #000000;\">(below) explains what each code represents and how the trend is most appropriately interpreted.<\/span><\/p><p><span style=\"color: #000000;\">\u2022 Index file:<\/span><br \/><span style=\"color: #000000;\">\u201cIndex\u201d is the annual index: calculated in logged form as part of generating the trend as a % per year change, <\/span><span style=\"color: #000000;\">then back-transformed to a more understandable estimate of average birds per day.<\/span><\/p><p><span style=\"color: #000000;\">\u2022 Index Plots:<\/span><br \/><span style=\"color: #000000;\">Trend information above each graph shows the long-term trend (% per year change), lower and upper CI, and<\/span> <span style=\"color: #000000;\">posterior probability, as defined above. Also shown (in parentheses following species name and season) is the <\/span><span style=\"color: #000000;\">analysis code that indicates what trend represents (See Table 1).<\/span><\/p><p><span style=\"color: #000000;\"><strong>Table 1. Key to Analysis Codes and interpretation of trends<\/strong><\/span><br \/><span style=\"color: #000000;\">M = regular migrant, 75+% of season covered by station in 2\/3 or more of all years. Analysis window limited to <\/span><span style=\"color: #000000;\">migratory surge, and few individuals are present before or after. Species is well-monitored at the site. Trends<\/span> <span style=\"color: #000000;\">are of good quality and represent change in population size for a large area of the station&#8217;s catchment area.<\/span><\/p><p><span style=\"color: #000000;\">ML = Similar to M, except that numbers before\/after migratory peak (i.e. local area birds) amount to more than <\/span><span style=\"color: #000000;\">a quarter of peak numbers during the migratory surge. Although the analysis window is limited to the period of <\/span><span style=\"color: #000000;\">migratory surge, the resulting trend can be strongly affected by local population level (which may or may not<\/span> <span style=\"color: #000000;\">agree with trend for birds migrating through the site). Note that \u201clocal area\u201d birds are those regularly observed <\/span><span style=\"color: #000000;\">at a station, though they may not breed or winter at the site itself.<\/span><\/p><p><span style=\"color: #000000;\">I = Irruptive and irregular migrants: species without a regular pattern of migratory movement. Analysis window<\/span><br \/><span style=\"color: #000000;\">covers the period in which there is at least occasional movement, but much of movement may fall outside of <\/span><span style=\"color: #000000;\">station coverage. Annual indices represent annual variation in extent and timing of irruption. Over the long <\/span><span style=\"color: #000000;\">term, population trends may be discernible despite the high degree of annual variation, but should be<\/span> <span style=\"color: #000000;\">interpreted case by case.<\/span><\/p><p><span style=\"color: #000000;\">L = Birds from local area (not necessarily breeding or wintering at count site per se, but regularly observed <\/span><span style=\"color: #000000;\">there), lacking seasonal patterns suggestive of through movement. Trends are assumed to reflect population<\/span> <span style=\"color: #000000;\">change in the local area, which may or may not agree with trends at broader geographic scales.<\/span><\/p><p><span style=\"color: #000000;\">S = Staging species (usually waterfowl and shorebirds) with pattern of migratory surge of which 75% or more of <\/span><span style=\"color: #000000;\">the movement period is covered by the station. Some \u2018S\u2019 species could be changed to \u2018M\u2019 if there is evidence <\/span><span style=\"color: #000000;\">that their movements are unidirectional and there is minimal stopover. In most cases, however, trends may <\/span><span style=\"color: #000000;\">represent site use rather than population change, as there may be annual variation in use of the specialized<\/span> <span style=\"color: #000000;\">stopover sites in the region, only one of which is being monitored. Trends should be interpreted case by case.<\/span><\/p><p><span style=\"color: #000000;\">MX = Regular migrant, but coverage at site falls short of documenting 75% of migration period. Shifts in timing <\/span><span style=\"color: #000000;\">of migration are not detectable from the data (e.g. change in timing due to climate change could produce a<\/span> <span style=\"color: #000000;\">trend that is independent of true population size.) This is a subclass of &#8220;O&#8221; species, but is designated separately <\/span><span style=\"color: #000000;\">to draw attention to species that could become \u2018M\u2019 with more extended coverage.<\/span><\/p><p><span style=\"color: #000000;\">O = Other, for species that do not fit into any of the above groups. Individuals may represent one or a <\/span><span style=\"color: #000000;\">combination of categories: casual visitation, premigratory dispersal, departing winter populations, or others. <\/span><span style=\"color: #000000;\">Trends very unlikely to represent population change either at a broad scale or in a definable local population.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Barn Swallow: A Report Purpose of this writing We have heard that Barn Swallows are on the list of Species at Risk. In many areas they are still quite common, and it is often difficult to recognize that their population is in decline. I wrote this essay to explain why they are listed as \u201cthreatened\u201d [&hellip;]<\/p>\n","protected":false},"author":7,"featured_media":0,"parent":85,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_seopress_robots_primary_cat":"","_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"disabled","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"class_list":["post-6956","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/pibo.ca\/en\/wp-json\/wp\/v2\/pages\/6956","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pibo.ca\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/pibo.ca\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/pibo.ca\/en\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/pibo.ca\/en\/wp-json\/wp\/v2\/comments?post=6956"}],"version-history":[{"count":22,"href":"https:\/\/pibo.ca\/en\/wp-json\/wp\/v2\/pages\/6956\/revisions"}],"predecessor-version":[{"id":26870,"href":"https:\/\/pibo.ca\/en\/wp-json\/wp\/v2\/pages\/6956\/revisions\/26870"}],"up":[{"embeddable":true,"href":"https:\/\/pibo.ca\/en\/wp-json\/wp\/v2\/pages\/85"}],"wp:attachment":[{"href":"https:\/\/pibo.ca\/en\/wp-json\/wp\/v2\/media?parent=6956"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}