Menard Jayme, Cossette Shayna N, Stewart Julee, Somers Christopher M
Department of Biology, University of Regina, Regina, SK, Canada.
BMC Zool. 2025 Mar 26;10(1):8. doi: 10.1186/s40850-025-00228-0.
The Prussian carp (Carassius gibelio) is an invasive fish species from Eurasia that was first found in North America in the Canadian province of Alberta in the early 2000s. In 2018, an established population of Prussian carp was discovered in the neighboring province of Saskatchewan, raising concern for additional spread in Canada and to the USA.
Prussian carp in Saskatchewan have colonized the South Saskatchewan River and tributaries and are moving towards additional connected systems to the northeast. Direct access to most of southern Saskatchewan and the USA is currently prevented only by the Qu'Appelle Dam on the South Saskatchewan River at Lake Diefenbaker. Prussian carp populations in Saskatchewan were age-stratified and ranged from hatch size (20 mm) to a maximum of 42.5 cm total length. Aging using otoliths and scales was unreliable, but the largest fish collected were likely > 10 years old. Saskatchewan Prussian carp had mixed ploidies with diploid, triploid, and tetraploid individuals intermixed. In Lake Diefenbaker, only adult female and juvenile fish were detected, but males were present in the Anerley Lakes at low relative abundance. Emergence of young of the year Prussian carp began in early July and continued through August, indicating an extended period of reproduction; however, most spawning likely occurred during mid-June. The timing of spawning overlaps with that of a variety of native sucker and shiner species, but sperm donors for potential gynogenesis remain unidentified.
Our findings suggest that invasive Prussian carp are well established in Saskatchewan and will likely use provincial waterbodies as a conduit to colonize more areas in North America.
欧鲫（Carassius gibelio）是一种来自欧亚大陆的入侵鱼类，21世纪初首次在北美洲加拿大的艾伯塔省被发现。2018年，在相邻的萨斯喀彻温省发现了一个已定居的欧鲫种群，这引发了人们对其在加拿大进一步扩散以及扩散到美国的担忧。
萨斯喀彻温省的欧鲫已在南萨斯喀彻温河及其支流中定殖，并正朝着向东北方向的其他相连水系移动。目前，萨斯喀彻温省南部大部分地区与美国之间的直接通道仅被迪芬贝克湖的南萨斯喀彻温河上的夸阿佩尔大坝阻断。萨斯喀彻温省的欧鲫种群按年龄分层，体长从刚孵化时的20毫米到最大全长42.5厘米不等。使用耳石和鳞片进行年龄鉴定不可靠，但所采集到的最大的鱼可能超过10岁。萨斯喀彻温省的欧鲫具有混合倍性，二倍体、三倍体和四倍体个体混杂在一起。在迪芬贝克湖，仅检测到成年雌鱼和幼鱼，但在阿内利湖中有少量雄鱼。当年幼鱼在7月初开始出现，并持续到8月，这表明繁殖期延长；然而，大多数产卵可能发生在6月中旬。产卵时间与多种本地吸盘鱼和闪亮鱼的产卵时间重叠，但潜在雌核发育的精子供体仍未确定。
我们的研究结果表明，入侵的欧鲫在萨斯喀彻温省已很好地定殖，并可能利用该省的水体作为渠道，在北美开拓更多区域。
