A synthesis of a coastal northern pike (Esox lucius) fishery and its social-ecological environment in the southern Baltic Sea: Implications for the management of mixed commercial-recreational fisheries

Arlinghaus, Robert; Rittweg, Timo; Dhellemmes, Félicie; Koemle, Dieter; Gemert, Rob van; Schubert, Hendrik; Niessner, Dominique; Möller, Sören; Droll, Jan; Friedland, René; Lewin, Wolf-Christian; Dorow, Malte; Westphal, Linda; Ehrlich, Elias; Strehlow, Harry Vincent; Weltersbach, Marc Simon; Roser, Phillip; Braun, Marlon Alexander; Feldhege, Fritz; Winkler, Helmut G. F.

doi:10.1016/j.fishres.2023.106663

Cited by 12 publications

(6 citation statements)

References 196 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Further, pike in our system were relatively stationary (mean size of extended home range: 6.58 km ± 5.77 km; Dhellemmes et al, 2023). Movement between freshwater and tributaries was relatively rare (6%; Möller et al, 2019) and usually only for short periods of less than 14 days (Arlinghaus et al, 2023a), which was likely too short to cause a shift in δ 18 O Otolith values.…”

Section: Age Corroboration and The Value Of Scalesmentioning

confidence: 77%

“…Coastal pike stocks in the Baltic Sea have traditionally been exploited by commercial fisheries, but a strong recreational fishery has recently developed (Arlinghaus et al, 2023b;Bergström et al, 2022) that often has different objectives than commercial fisheries, such as favoring the catch of trophy fish or catch rate over biomass yield (Ahrens et al, 2020;Arlinghaus et al, 2019). Over the last decade, pike stocks have declined in many areas of the Baltic (Bergström et al, 2022;Fitzgerald et al, 2023;Lehtonen et al, 2009;Olsson et al, 2023).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Corroborating otolith age using oxygen isotopes and comparing outcomes to scale age: Consequences for estimation of growth and reference points in northern pike (Esox lucius)

Rittweg

Trueman

Ehrlich

et al. 2023

Fisheries Management Eco

Self Cite

View full text Add to dashboard Cite

Accurate age estimates are crucial for assessing the life‐histories of fish and providing management advice, but validation studies are rare for many species. We corroborated age estimates with annual cycles of oxygen isotopes (δ18O) in otoliths of 86 northern pike (Esox lucius) from the southern Baltic Sea, compared results with visual age estimates from scales and otoliths, and assessed bias introduced by different age‐estimation structures on von Bertalanffy growth models and age‐structured population models. Age estimates from otoliths were accurate, while age estimates from scales significantly underestimated the age of pike older than 6 years compared to the corroborated reference age. Asymptotic length () was larger, and the growth coefficient was lower for scale ages than for corroborated age and otolith age estimates. Consequentially, scale‐informed population models overestimated maximum sustainable yield (), biomass at (), relative frequency of trophy fish (), and optimal minimum length limit but underestimated fishing mortality at (). Using scale‐based ages to inform management regulations for pike may therefore result in conservative management and lost yield. The overestimated asymptotic length may instill unrealistic expectations of trophy potential in recreational anglers targeting large pike, while the overestimation in MSY would cause unrealistic expectations of yield potential in commercial fishers.

show abstract

Section: Age Corroboration and The Value Of Scalesmentioning

confidence: 77%

mentioning

confidence: 99%

Corroborating otolith age using oxygen isotopes and comparing outcomes to scale age: Consequences for estimation of growth and reference points in northern pike (Esox lucius)

Rittweg

Trueman

Ehrlich

et al. 2023

Fisheries Management Eco

Self Cite

View full text Add to dashboard Cite

show abstract

“…1). As a result of geographical characteristics of the region (e.g., varying patterns of land barriers between lagoons and open Baltic Sea and freshwater discharge from rivers), these lagoons exhibit significant hydrochemical variability, including salinity, water temperature, Secchi depth, and nutrient concentrations (supplementary materials, Table S1) (Arlinghaus et al 2023b). The most pronounced is the salinity gradient, with higher salinity levels in the northwest mesohaline areas (e.g., in Vitter, Schaproder, and Kubitzer Bodden) and lower salinity levels in the southeast oligohaline lagoons (Peenestrom and Stettiner Haff).…”

Section: Study Areamentioning

confidence: 99%

“…The Baltic Sea is one of the world's largest brackish water bodies, characterized by a strong salinity gradient from sea salinity (30 practical salinity units, PSU) in its western part, connected to the North Sea, to almost fresh water (2 PSU) in the northeast (Schubert et al 2017). In addition, at local levels, salinity gradients are pronounced, especially in nearshore coastal areas, such as, for example, a lagoon network around the island of Rügen, Germany, in the southern Baltic Sea, where salinities in different lagoons can range from almost freshwater oligohaline (< 5 PSU) to mesohaline conditions (< 12 PSU) (Arlinghaus et al 2023b). These regional and local ecological gradients in salinity have shaped a unique species assemblage, comprising marine, estuarine, and freshwater species (Wennerström et al 2013).…”

Section: Introductionmentioning

confidence: 99%

“…We hypothesized that the pike population in the study area around the island of Rügen, Germany (see Arlinghaus et al 2023b for a full review) is (H1) composed of several subpopulations with relatively stationary space use and low ecological connectivity among them, (H2) shows spawning site fidelity and behaviorally differentiated ecotypes, and (H3) its genetic structure is driven both by limited ecological connectivity and by environmental factors such as salinity gradients and geographic distances.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Combining biotelemetry and genetics provides complementary insights relevant to the management and conservation of a freshwater predator (Esox lucius) living in brackish lagoons

Lukyanova,

Dhellemmes,

Dennenmoser

et al. 2024

Aquat Sci

Self Cite

View full text Add to dashboard Cite

To inform the management of wild fish populations, it is equally important to understand both the ecological connectivity of habitat patches, apparent at annual and seasonal scales, and the genetic connectivity, emerging at evolutionary scales across generations. Ecological connectivity indicates the potential for rapid recolonization upon local depletion, while genetic connectivity informs about the conservation needs related to the evolution of subpopulations and ecotypes in metapopulations. We combined acoustic biotelemetry and pooled-genome sequencing to study a northern pike (Esox lucius) population as a model of a freshwater piscivore that inhabits a network of shallow brackish lagoons in the southern Baltic Sea. We found limited ecological connectivity among genetically similar subpopulations of pike, suggesting a metapopulation structure characterized by discrete local subpopulations with infrequent migrations between them. Connectivity of different lagoons increased during spawning, suggesting directed spawning migrations to either freshwater rivers or low salinity patches in connected lake-like bays. Spawning site fidelity to either brackish or freshwater spawning sites was observed, further contributing to the reproductive isolation of certain subpopulations. The genetic population structure aligned with salinity gradients and geographical distance and was significant between pairs of rivers draining into the lagoon network, but it was unrelated to ecological connectivity. The results collectively suggest that local subpopulations may not rapidly replenish upon local depletion and that even weak connectivity among subpopulations was sufficient to maintain genetic homogeneity across lagoons with similar salinity levels. Effective management and conservation of species forming metapopulations, such as the coastal northern pike studied here, necessitate localized approaches that adapt fishing mortality to local abundance and promote access to specific habitats, especially rivers, during spawning to conserve the entire genetic biodiversity and foster resilience of the metapopulation.

show abstract

Variable habitat use supports fine-scale population differentiation of a freshwater piscivore (northern pike, Esox lucius) along salinity gradients in brackish lagoons

Rittweg,

Trueman,

Wiedenbeck

et al. 2024

Oecologia

View full text Add to dashboard Cite

In mobile animals, selection pressures resulting from spatio-temporally varying ecological factors often drive adaptations in migration behavior and associated physiological phenotypes. These adaptations may manifest in ecologically and genetically distinct ecotypes within populations. We studied a meta-population of northern pike (Esox lucius) in brackish environments and examined intrapopulation divergence along environmental gradients. Behavioral phenotypes in habitat use were characterized via otolith microchemistry in 120 individuals sampled from brackish lagoons and adjacent freshwater tributaries. We genotyped 1514 individual pike at 33 highly informative genetic markers. The relationship between behavioral phenotype and genotype was examined in a subset of 101 pikes for which both phenotypic and genomic data were available. Thermosaline differences between juvenile and adult life stages indicated ontogenetic shifts from warm, low-saline early habitats towards colder, higher-saline adult habitats. Four behavioral phenotypes were found: Freshwater residents, anadromous, brackish residents, and cross-habitat individuals, the latter showing intermediary habitat use between brackish and freshwater areas. Underlying the behavioral phenotypes were four genotypes, putative freshwater, putative anadromous, and two putatively brackish genotypes. Through phenotype-genotype matching, three ecotypes were identified: (i) a brackish resident ecotype, (ii) a freshwater ecotype expressing freshwater residency or anadromy, and (iii) a previously undescribed intermediary cross-habitat ecotype adapted to intermediate salinities, showing limited reliance on freshwater. Life-time growth of all ecotypes was similar, suggesting comparable fitness. By combining genetic data with lifelong habitat use and growth as a fitness surrogate, our study revealed strong differentiation in response to abiotic environmental gradients, primarily salinity, indicating ecotype diversity in coastal northern pike is higher than previously believed. Graphical abstract

show abstract

A synthesis of a coastal northern pike (Esox lucius) fishery and its social-ecological environment in the southern Baltic Sea: Implications for the management of mixed commercial-recreational fisheries

Cited by 12 publications

References 196 publications

Corroborating otolith age using oxygen isotopes and comparing outcomes to scale age: Consequences for estimation of growth and reference points in northern pike (Esox lucius)

Corroborating otolith age using oxygen isotopes and comparing outcomes to scale age: Consequences for estimation of growth and reference points in northern pike (Esox lucius)

Combining biotelemetry and genetics provides complementary insights relevant to the management and conservation of a freshwater predator (Esox lucius) living in brackish lagoons

Variable habitat use supports fine-scale population differentiation of a freshwater piscivore (northern pike, Esox lucius) along salinity gradients in brackish lagoons

Contact Info

Product

Resources

About