{"id":3075,"date":"2015-08-05T13:49:25","date_gmt":"2015-08-05T11:49:25","guid":{"rendered":"http:\/\/blogs.sun.ac.za\/cib\/?p=3075"},"modified":"2020-09-16T14:49:29","modified_gmt":"2020-09-16T12:49:29","slug":"movement-mysteries-of-largemouth-bass","status":"publish","type":"post","link":"https:\/\/blogs.sun.ac.za\/cib\/movement-mysteries-of-largemouth-bass\/","title":{"rendered":"Movement mysteries of largemouth bass"},"content":{"rendered":"<p>Largemouth bass (<em>Micropterus salmoides<\/em>) are a popular and valuable sport-fish for anglers. They were introduced into South Africa in 1928, and have since been widely distributed across southern Africa. \u00a0A predatory species, largemouth bass are a threat to native fishes, frogs and aquatic insects. Recreational fisheries are focussed mainly on populations in impoundments while biodiversity concerns are primarily in rivers. Understanding how largemouth bass move between impoundments and inflowing rivers is therefore essential for managing invasions.<\/p>\n<p>To better understand largemouth bass movement behaviour, students Carl Huchzermeyer and Dylan Howell from C\u00b7I\u00b7B Core Team Member Dr Olaf Weyl\u2019s freshwater research team at the <a href=\"http:\/\/www.saiab.ac.za\/\" target=\"_blank\" rel=\"noopener noreferrer\">South African Institute for Aquatic Biodiversity (SAIAB<\/a>), undertook biotelemetry studies in the Kabusi arm of Wriggleswade Dam in the Eastern Cape. Acoustic transmitters were surgically inserted into largemouth bass and their movements were tracked over a 9-month period using an array of receivers (listening stations) in the Wriggleswade Dam.<\/p>\n<figure id=\"attachment_3076\" aria-describedby=\"caption-attachment-3076\" style=\"width: 760px\" class=\"wp-caption aligncenter\"><img fetchpriority=\"high\" decoding=\"async\" class=\"size-full wp-image-3076\" src=\"http:\/\/blogs.sun.ac.za\/cib\/files\/2020\/09\/acoustic-transmitter.png\" alt=\"Surgical insertion of acoustic transmitters into largemouth bass\" width=\"760\" height=\"570\" srcset=\"https:\/\/blogs.sun.ac.za\/cib\/files\/2020\/09\/acoustic-transmitter.png 760w, https:\/\/blogs.sun.ac.za\/cib\/files\/2020\/09\/acoustic-transmitter-580x435.png 580w, https:\/\/blogs.sun.ac.za\/cib\/files\/2020\/09\/acoustic-transmitter-400x300.png 400w\" sizes=\"(max-width: 760px) 100vw, 760px\" \/><figcaption id=\"caption-attachment-3076\" class=\"wp-caption-text\">Surgical insertion of acoustic transmitters into largemouth bass (Photo credit: Olaf Weyl)<\/figcaption><\/figure>\n<p>Analyses showed seasonal patterns of area use of regions of different depths, and indicated that fish positions were influenced by water temperature and river inflow. Fish moved into deeper regions in the main body of the impoundments at the beginning of winter and moved back into shallow regions near the river inlet with warmer temperatures at the beginning of summer.<\/p>\n<blockquote><p>\u201c<em>The results from this study highlighted the importance of environmental factors, particularly water temperature, on the movement of largemouth bass<\/em>.\u201d says Olaf Weyl. \u201c<em>It may explain why &#8211; in winter rainfall regions largemouth bass are seldom found in small headwater rivers<\/em>.\u201d These results are important for the management of largemouth bass because they allow for an assessment of the risks associated with introductions in main stem impoundments.<\/p><\/blockquote>\n<h4>Read the papers<\/h4>\n<p><a href=\"http:\/\/www.tandfonline.com\/doi\/pdf\/10.1080\/15627020.2015.1040837\" target=\"_blank\" rel=\"noopener noreferrer\">Howell D, Childs AR, Cowley PD, Weyl OLF. (2015) Movement behaviour of largemouth bass\u00a0<em>Micropterus salmoides<\/em>\u00a0in a South African impoundment. African Zoology. DOI: 10.1080\/15627020.2015.1040837<\/a><\/p>\n<p><a href=\"http:\/\/www.tandfonline.com\/doi\/pdf\/10.2989\/16085914.2012.752716\" target=\"_blank\" rel=\"noopener noreferrer\">Huchzermeyer CF, Weyl OLF, Cowley PD. (2013) Evaluation of acoustic transmitter implantation and determination of post-translocation behaviour of largemouth bass <em>Micropterus salmoides <\/em>in a South African impoundment. <em>African Journal of Aquatic Science 2013, 38(2): 229-236. <\/em>DOI: 10.2989\/16085914.2012.752716<\/a><\/p>\n<p>For more information, contact Olaf Weyl at <a href=\"mailto:O.Weyl@saiab.ac.za\">O.Weyl@saiab.ac.za<\/a><\/p>\n<figure id=\"attachment_3077\" aria-describedby=\"caption-attachment-3077\" style=\"width: 733px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" class=\"size-full wp-image-3077\" src=\"http:\/\/blogs.sun.ac.za\/cib\/files\/2020\/09\/bass-tracking.png\" alt=\"The movements of the bass were tracked over a 9-month period using several receivers\" width=\"733\" height=\"550\" srcset=\"https:\/\/blogs.sun.ac.za\/cib\/files\/2020\/09\/bass-tracking.png 733w, https:\/\/blogs.sun.ac.za\/cib\/files\/2020\/09\/bass-tracking-580x435.png 580w, https:\/\/blogs.sun.ac.za\/cib\/files\/2020\/09\/bass-tracking-400x300.png 400w\" sizes=\"(max-width: 733px) 100vw, 733px\" \/><figcaption id=\"caption-attachment-3077\" class=\"wp-caption-text\">The movements of the bass were tracked over a 9-month period using several receivers. (Photo credit: Olaf Weyl)<\/figcaption><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Largemouth bass (Micropterus salmoides) are a popular and valuable sport-fish for anglers. They were introduced into South Africa in 1928, and have since been widely distributed across southern Africa.<\/p>\n","protected":false},"author":237,"featured_media":3076,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"ocean_post_layout":"","ocean_both_sidebars_style":"","ocean_both_sidebars_content_width":0,"ocean_both_sidebars_sidebars_width":0,"ocean_sidebar":"","ocean_second_sidebar":"","ocean_disable_margins":"enable","ocean_add_body_class":"","ocean_shortcode_before_top_bar":"","ocean_shortcode_after_top_bar":"","ocean_shortcode_before_header":"","ocean_shortcode_after_header":"","ocean_has_shortcode":"","ocean_shortcode_after_title":"","ocean_shortcode_before_footer_widgets":"","ocean_shortcode_after_footer_widgets":"","ocean_shortcode_before_footer_bottom":"","ocean_shortcode_after_footer_bottom":"","ocean_display_top_bar":"default","ocean_display_header":"default","ocean_header_style":"","ocean_center_header_left_menu":"","ocean_custom_header_template":"","ocean_custom_logo":0,"ocean_custom_retina_logo":0,"ocean_custom_logo_max_width":0,"ocean_custom_logo_tablet_max_width":0,"ocean_custom_logo_mobile_max_width":0,"ocean_custom_logo_max_height":0,"ocean_custom_logo_tablet_max_height":0,"ocean_custom_logo_mobile_max_height":0,"ocean_header_custom_menu":"","ocean_menu_typo_font_family":"","ocean_menu_typo_font_subset":"","ocean_menu_typo_font_size":0,"ocean_menu_typo_font_size_tablet":0,"ocean_menu_typo_font_size_mobile":0,"ocean_menu_typo_font_size_unit":"px","ocean_menu_typo_font_weight":"","ocean_menu_typo_font_weight_tablet":"","ocean_menu_typo_font_weight_mobile":"","ocean_menu_typo_transform":"","ocean_menu_typo_transform_tablet":"","ocean_menu_typo_transform_mobile":"","ocean_menu_typo_line_height":0,"ocean_menu_typo_line_height_tablet":0,"ocean_menu_typo_line_height_mobile":0,"ocean_menu_typo_line_height_unit":"","ocean_menu_typo_spacing":0,"ocean_menu_typo_spacing_tablet":0,"ocean_menu_typo_spacing_mobile":0,"ocean_menu_typo_spacing_unit":"","ocean_menu_link_color":"","ocean_menu_link_color_hover":"","ocean_menu_link_color_active":"","ocean_menu_link_background":"","ocean_menu_link_hover_background":"","ocean_menu_link_active_background":"","ocean_menu_social_links_bg":"","ocean_menu_social_hover_links_bg":"","ocean_menu_social_links_color":"","ocean_menu_social_hover_links_color":"","ocean_disable_title":"default","ocean_disable_heading":"default","ocean_post_title":"","ocean_post_subheading":"","ocean_post_title_style":"","ocean_post_title_background_color":"","ocean_post_title_background":0,"ocean_post_title_bg_image_position":"","ocean_post_title_bg_image_attachment":"","ocean_post_title_bg_image_repeat":"","ocean_post_title_bg_image_size":"","ocean_post_title_height":0,"ocean_post_title_bg_overlay":0.5,"ocean_post_title_bg_overlay_color":"","ocean_disable_breadcrumbs":"default","ocean_breadcrumbs_color":"","ocean_breadcrumbs_separator_color":"","ocean_breadcrumbs_links_color":"","ocean_breadcrumbs_links_hover_color":"","ocean_display_footer_widgets":"default","ocean_display_footer_bottom":"default","ocean_custom_footer_template":"","ocean_post_oembed":"","ocean_post_self_hosted_media":"","ocean_post_video_embed":"","ocean_link_format":"","ocean_link_format_target":"self","ocean_quote_format":"","ocean_quote_format_link":"post","ocean_gallery_link_images":"on","ocean_gallery_id":[],"footnotes":""},"categories":[73242,3256],"tags":[73354,71773,71637,73355,71829,71688],"class_list":["post-3075","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-2015-news","category-news","tag-acoustic-telemetry","tag-alien-invasive","tag-ecology","tag-flow","tag-largemouth-bass","tag-temperature","entry","has-media"],"acf":[],"_links":{"self":[{"href":"https:\/\/blogs.sun.ac.za\/cib\/wp-json\/wp\/v2\/posts\/3075","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.sun.ac.za\/cib\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.sun.ac.za\/cib\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.sun.ac.za\/cib\/wp-json\/wp\/v2\/users\/237"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.sun.ac.za\/cib\/wp-json\/wp\/v2\/comments?post=3075"}],"version-history":[{"count":1,"href":"https:\/\/blogs.sun.ac.za\/cib\/wp-json\/wp\/v2\/posts\/3075\/revisions"}],"predecessor-version":[{"id":3078,"href":"https:\/\/blogs.sun.ac.za\/cib\/wp-json\/wp\/v2\/posts\/3075\/revisions\/3078"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.sun.ac.za\/cib\/wp-json\/wp\/v2\/media\/3076"}],"wp:attachment":[{"href":"https:\/\/blogs.sun.ac.za\/cib\/wp-json\/wp\/v2\/media?parent=3075"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.sun.ac.za\/cib\/wp-json\/wp\/v2\/categories?post=3075"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.sun.ac.za\/cib\/wp-json\/wp\/v2\/tags?post=3075"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}