Kouba Antonín, Lipták Boris, Kubec Jan, Bláha Martin, Veselý Lukáš, Haubrock Phillip J, Oficialdegui Francisco J, Niksirat Hamid, Patoka Jiří, Buřič Miloš
South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in České Budějovice, Zátiší 728/II, 38925 Vodňany, Czech Republic.
Department of River Ecology and Conservation, Senckenberg Research Institute and Natural History Museum Frankfurt, Clamecystrasse 12, 63571 Gelnhausen, Germany.
Biology (Basel). 2021 May 10;10(5):422. doi: 10.3390/biology10050422.
Biological invasions are increasingly recognized ecological and economic threats to biodiversity and are projected to increase in the future. Introduced freshwater crayfish in particular are protruding invaders, exerting tremendous impacts on native biodiversity and ecosystem functioning, as exemplified by the North American spiny-cheek, signal and red swamp crayfish as well as the Australian common yabby. The marbled crayfish is among the most outstanding freshwater crayfish invaders due to its parthenogenetic reproduction combined with early maturation and high fecundity. As their introduced ranges expand, their sympatric populations become more frequent. The question of which species and under what circumstances will dominate in their introduced communities is of great interest to biodiversity conservation as it can offer valuable insights for understanding and prioritization of management efforts. In order to examine which of the aforementioned species may be more successful as an invader, we conducted a set of independent trials evaluating survival, growth, claw injury, and reproduction using single-species stocks (intraspecific interactions) and mixed stocks (interspecific interactions) of marbled crayfish vs. other crayfish invaders since the onset of exogenous feeding. In both single and mixed stocks, red swamp crayfish and yabby grew faster than marbled crayfish, while marbled crayfish were superior to both spiny-cheek and signal crayfish in terms of growth. With the exception of signal crayfish, the faster-growing species consistently reached a higher survival rate. The faster-growing species tended to negatively impair smaller counterparts by greater claw injury, delayed maturation, and reduced fecundity. Only marbled crayfish laid eggs as early as 14 weeks in this study, which is earlier than previously reported in the literature. Thus, the success of marbled crayfish among invasive crayfish is significantly driven by relatively fast growth as well as an early and frequent reproduction. These results shed light on how interactions between invasive populations can unfold when their expansion ranges overlap in the wild, thereby contributing to the knowledge base on the complex population dynamics between existing and emerging invasive species.
生物入侵日益被视为对生物多样性的生态和经济威胁，预计未来还会增加。特别是引进的淡水小龙虾是突出的入侵者，对本地生物多样性和生态系统功能产生巨大影响，北美刺颊小龙虾、信号小龙虾、红沼泽小龙虾以及澳大利亚普通螯虾就是例证。大理石纹螯虾因其孤雌生殖、早熟和高繁殖力，成为最突出的淡水小龙虾入侵者之一。随着其引入范围的扩大，它们的同域种群变得更加常见。在其引入的群落中，哪种物种以及在何种情况下会占据主导地位的问题，对于生物多样性保护至关重要，因为它可以为理解和优先开展管理工作提供有价值的见解。为了研究上述哪种物种可能作为入侵者更成功，我们进行了一系列独立试验，自开始外源投喂以来，使用大理石纹螯虾与其他小龙虾入侵者的单物种种群（种内相互作用）和混合种群（种间相互作用）评估生存、生长、螯损伤和繁殖情况。在单种群和混合种群中，红沼泽小龙虾和螯虾的生长速度都比大理石纹螯虾快，而大理石纹螯虾在生长方面优于刺颊小龙虾和信号小龙虾。除了信号小龙虾外，生长较快的物种始终具有较高的存活率。生长较快的物种往往会通过更大的螯损伤、延迟成熟和降低繁殖力对较小的同类产生负面影响。在本研究中，只有大理石纹螯虾早在14周就产卵，这比之前文献报道的时间更早。因此，大理石纹螯虾在入侵小龙虾中的成功显著得益于相对较快的生长以及早期和频繁的繁殖。这些结果揭示了入侵种群在野外扩张范围重叠时，它们之间的相互作用是如何展开的，从而为现有和新出现的入侵物种之间复杂的种群动态知识库做出了贡献。
