Estimating Seasonal Movements of Chinook Salmon in Lake Huron from Efficiency Analysis of Coded Wire Tag Recoveries in Recreational Fisheries

The decline of hatchery‐reared Chinook salmon Oncorhynchus tshawytscha stocks in Lakes Huron and Michigan during the 1980s prompted mass‐tagging programs to investigate reproduction, poststocking survival, and movements. In Lake Huron, millions of smolts implanted with coded wire tags (CWTs) were released in Michigan waters and recovered from charter and noncharter fisheries, surveys, and weirs. Using generalized linear models (GLMs), we investigated Chinook salmon seasonal movements based on the spatial and temporal distributions of recoveries by fishing trips in U.S. recreational fisheries and recovery efficiency. We used models incorporating area, month, year, and recovery source; creel‐clerk and “headhunter” (CWT collection specialist) samples; and charter captain reports. We implemented models for recoveries regardless of release area and from one particular area. All model predictors and interactions between month and area were significant. The variation in recovery levels among recovery sources was larger than temporal or spatial variation. Headhunters were 7 times more efficient than captains in recovering CWTs from charter‐boat catch and 11 times more efficient than clerks in recovering CWTs from non‐charter‐boat catch; this was due to the higher catches experienced in charter than in noncharter trips and to different recovery program goals. The spatial and temporal distribution of GLM‐standardized recovery levels suggested that Chinook salmon released along the western coast of Lake Huron moved near shore during early spring and north during summer, returning mostly to nearby stocking areas in summer and fall. To complement our GLM analysis, we evaluated the distributions of CWT salmon released and recovered in U.S. and Canadian waters by all sources. Data supported previous conclusions on longitudinal movements and indicated that in spring fish moved from eastern locations to near shore in western Lake Huron then back to overwinter locations in autumn. These movement patterns coincided with seasonal prey species concentrations and favorable temperatures. The implications of our results for salmon fisheries management and the design of future tagging studies are discussed.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142006/1/nafm0792.pd

Seasonal Movements of Chinook Salmon in Lake Michigan Based on Tag Recoveries from Recreational Fisheries and Catch Rates in Gill‐Net Assessments

There are no specific studies of the movements of introduced Chinook salmon Oncorhynchus tshawytscha in Lake Michigan, despite the need for such information for population assessments and stocking allocations. We investigated the seasonal distribution of hatchery‐reared Chinook salmon between May and September based on fishery‐dependent (recoveries from recreational fisheries of fish marked with coded wire tags [CWTs]) and fishery‐independent sources (catches in assessment gill‐net surveys). We modeled recoveries by fishing trips in Michigan waters of Lake Michigan to estimate spatially and temporally explicit abundance indices using generalized linear models (GLMs) and accounted for the efficiency among recovery sources (charter boat captain reports, creel clerk interviews, and headhunter collections of CWT samples from charter boat and non‐charter boat catches). Recovery levels varied among areas, months, years, and recovery sources, and distribution among areas also varied by month. We used CWT data with lakewide geographical coverage and evaluated the distributions of the absolute numbers of coded‐wire‐tagged fish recovered in Michigan and Wisconsin waters of Lake Michigan from all possible recovery sources. From both analyses we found that the distribution of Chinook salmon varied seasonally, with displacements from southern areas toward the north from May through summer, from inshore to offshore areas toward the west during summer, and movement back east in the fall. For the analysis of Chinook salmon catch rates in gill‐net assessments, we used GLMs to compare levels among months, statistical districts, years, nearshore and offshore areas, and different depths. The temporal and spatial trends were similar to those from the CWT analyses, and the distribution shifted toward deeper waters in July and August. Movement patterns coincided with favorable temperature and prey distribution and were consistent with those exhibited by the Pacific Ocean Chinook salmon population from which the Lake Michigan population originated. Seasonal changes in Chinook salmon distribution influence recreational fisheries, and stocking strategies should consider the influences of movement patterns on fishing opportunities in Lake Michigan.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142273/1/tafs0736.pd

Florivory Shapes both Leaf and Floral Interactions

Florivory, or the consumption of flowers, is a ubiquitous interaction that can reduce plant reproduction directly by damaging reproductive tissues and indirectly by deterring pollinators. However, we know surprisingly little about how florivory alters plant traits or the larger community of species interactions. Although leaf damage is known to affect floral traits and interactions in many systems, the consequences of floral damage for leaf traits and interactions are unknown. We manipulated floral damage in Impatiens capensisand measured effects on floral attractive traits and secondary chemicals, leaf secondary chemicals, floral interactions, leaf herbivory, and plant reproduction. We also examined relationships between early season floral traits and floral interactions, to explore which traits structure floral interactions. Moderate but not high florivory significantly increased relative selfed reproduction, leading to a shift in mating system away from outcrossing. Florivory increased leaf secondary compounds and decreased leaf herbivory, although mechanisms other than leaf chemistry may be responsible for some of the reduced leaf damage. Florivory altered four of seven measured interactions, including increased subsequent florivory and reduced flower spiders, although only leaf damage effects were significant after correcting for multiple tests. Pretreatment concentrations of floral anthocyanins and condensed tannins were associated with reduced levels of many floral antagonisms, including florivory, nectar larceny, and flower spider abundance, suggesting these traits play a role in floral resistance. Overall, our results indicate a broad range of community and potential evolutionary consequences of florivory through structuring subsequent floral interactions, altering leaf secondary chemicals, and shaping leaf herbivory

Recovery of Wolverines in the Western United States: Recent Extirpation and Recolonization or Range Retraction and Expansion?

Wolverines were greatly reduced in number and possibly extirpated from the contiguous United States (U.S.) by the early 1900s. Wolverines currently occupy much of their historical range in Washington, Idaho, Montana, and Wyoming, but are absent from Utah and only single individuals are known to occur in California and Colorado. In response, the translocation of wolverines to California and Colorado is being considered. If wolverines are to be reintroduced, managers must identify appropriate source populations based on the genetic affinities of historical and modern wolverine populations. We amplified the mitochondrial control region of 13 museum specimens dating from the late 1800s to early 1900s and 209 wolverines from modern populations in the contiguous U.S. and Canada and combined results with previously published haplotypes. Collectively, these data indicated that historical wolverine populations in the contiguous U.S. were extirpated by the early 20th century, and that modern populations in the contiguous U.S. are likely the descendants of recent immigrants from the north. The Cali1 haplotype previously identified in California museum specimens was also common in historical samples from the southern Rocky Mountains, and likely evolved in isolation in the southern ice-free refugium that encompassed most of the contiguous U.S. during the last glaciation. However, when southern populations were extirpated, these matrilines were eliminated. Several of the other haplotypes found in historical specimens from the contiguous U.S. also occur in modern North American populations, and belong to a group of haplotypes that are associated with the rapid expansion of northern wolverine populations after the last glacial retreat. Modern wolverines in the contiguous U.S. are primarily haplotype A, which is the most common and widespread haplotype in Canada and Alaska. For the translocation of wolverines to California, Colorado, and other areas in the western U.S., potential source populations in the Canadian Rocky Mountains may provide the best mix of genetic diversity and appropriate learned behavior

Editorial: Application of network-theoretic approaches in biology

Biological complexity explicitly occurs through non-linear interactions mostly entangled in nature. This complexity comprises many interactions among entities (viz., genes, proteins, metabolites, and species) at various spatial and temporal scales as complex adaptive systems showing characteristic features like self-organisation, modularity, emergence, non-linear interactions, collective response, and adaptation. The theory of complex networks provides an appropriate formal framework for modelling of such complex systems in order to obtain meaningful insights into biological complexity at the local or gene family level (Mallikarjuna et al., 2020; Mallikarjuna et al., 2022) and at the global scale (Sharma et al., 2021). The ocean of biological data generated by high-throughput technologies in the current genomics era have led to the application of various network-theoretic empirical investigations, in which the formal framework is used to obtain meaningful insights into system complexity. Our effort to pool studies on network-theoretic approaches in biology to the understanding of biological complexity has resulted in the compilation of ten research studies in the current Research Topic entitled Application of network theoretic approaches in biology, which are broadly categorised and highlighted under the following headings

Development and Evaluation of a High Density Genotyping ‘Axiom_Arachis’ Array with 58 K SNPs for Accelerating Genetics and Breeding in Groundnut

Single nucleotide polymorphisms (SNPs) are the most abundant DNA sequence variation in the genomes which can be used to associate genotypic variation to the phenotype. Therefore, availability of a high-density SNP array with uniform genome coverage can advance genetic studies and breeding applications. Here we report the development of a high-density SNP array ‘Axiom_Arachis’ with 58 K SNPs and its utility in groundnut genetic diversity study. In this context, from a total of 163,782 SNPs derived from DNA resequencing and RNA-sequencing of 41 groundnut accessions and wild diploid ancestors, a total of 58,233 unique and informative SNPs were selected for developing the array. In addition to cultivated groundnuts (Arachis hypogaea), fair representation was kept for other diploids (A. duranensis, A. stenosperma, A. cardenasii, A. magna and A. batizocoi). Genotyping of the groundnut ‘Reference Set’ containing 300 genotypes identified 44,424 polymorphic SNPs and genetic diversity analysis provided in-depth insights into the genetic architecture of this material. The availability of the high-density SNP array ‘Axiom_Arachis’ with 58 K SNPs will accelerate the process of high resolution trait genetics and molecular breeding in cultivated groundnut