1.0Swiss Ornithological Institutehttps://www.vogelwarte.ch/en/rich600338<blockquote class="wp-embedded-content" data-secret="IvsGaShUdo"><a href="https://www.vogelwarte.ch/en/birds-of-switzerland/sand-martin/">Sand Martin</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://www.vogelwarte.ch/en/birds-of-switzerland/sand-martin/embed/#?secret=IvsGaShUdo" width="600" height="338" title="“Sand Martin” — Swiss Ornithological Institute" data-secret="IvsGaShUdo" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script> /*! This file is auto-generated */ !function(d,l){"use strict";l.querySelector&&d.addEventListener&&"undefined"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!/[^a-zA-Z0-9]/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),o=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),c=new RegExp("^https?:$","i"),i=0;i<o.length;i++)o[i].style.display="none";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute("style"),"height"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):"link"===t.message&&(r=new URL(s.getAttribute("src")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",function(){for(var e,t,s=l.querySelectorAll("iframe.wp-embedded-content"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute("data-secret"))||(t=Math.random().toString(36).substring(2,12),e.src+="#?secret="+t,e.setAttribute("data-secret",t)),e.contentWindow.postMessage({message:"ready",secret:t},"*")},!1)))}(window,document); //# sourceURL=https://www.vogelwarte.ch/wp-includes/js/wp-embed.min.js </script> https://www.vogelwarte.ch/wp-content/uploads/2026/03/3650_1.jpg16001200In Switzerland the Collared Sand Martin breeds in colonies in gravel pits, whereas it used to breed in steep banks of naturally-flowing rivers. There is a lively coming and going in the breeding colonies, which can accommodate up to more than 100 breeding birds. The air is mostly full of the calls of numerous Collared Sand Martins chattering to each other or flying to their nest entrances. They use their feet to dig the up to one metre long nest tunnels. If tunnels in large colonies are left unguarded, nesting material is often stolen by neighbours.