Chris Harrod

University of Glasgow | UofG · School of Biodiversity One

Similar environmental driving forces can produce similarity among geographically distant ecosystems. Coastal oceanic upwelling, for example, has been associated with elevated biomass and abundance patterns of certain functional groups, e.g., corticated macroalgae. In the upwelling system of Northern Chile, we examined measures of intertidal macro-b...

Coastal marine upwelling famously supports elevated levels of pelagic biological production, but can also subsidise production in inshore habitats via pelagic-benthic coupling. Consumers inhabiting macroalgae-dominated rocky reef habitats are often considered to be members of a food web fuelled by energy derived from benthic primary production; con...

Jellyfish are increasingly topical within studies of marine food webs. Stable isotope analysis represents a valuable technique to unravel the complex trophic role of these long-overlooked species. In other taxa, sample preservation has been shown to alter the isotopic values of species under consideration, potentially leading to misinterpretation o...

This study presents phylogenetic molecular data of the Chilean species of Orestias to propose an allopatric divergence hypothesis and phylogeographic evidence that suggests the relevance of abiotic factors in promoting population divergence in this complex. The results reveal that diversification is still ongoing, e.g. in the Ascotán salt pan, wher...

On the flanks of > 6000 m Andean volcanoes that tower over the Atacama Desert, leaf‐eared mice (Phyllotis vaccarum) live at extreme elevations that surpass known vegetation limits. The diet of these mice in these barren, hyperarid environments has been the subject of much speculation. According to the arthropod fallout hypothesis, sustenance is pro...

Pinnipeds face increasing challenges which affect how maternal foraging and nursing strategies transfer key resources for immune function and ultimately the survival of their offspring. We evaluated how foraging strategies and maternal care in South American fur seals (Arctocephalus australis) affect male and female pup growth, physiology and immun...

Rainbow trout (Oncorhynchus mykiss) have been widely introduced outside of their natural range and are one of the World’s most invasive species. Illegally introduced into the isolated, high-altitude (4520 m) Chungará catchment of northern Chile, rainbow trout have now been present in the system for ∼30 years and to our knowledge are the World’s hig...

Saline and hypersaline wetlands are biodiversity hotspots for metazoans such as aquatic invertebrates and wading birds. However, the survival of these habitats and their biota is increasingly threatened by a combination of pressures from climate change and extractive processes, jeopardizing the long-term ecological functioning of these ecosystems....

Marked environmental changes occurred in the southern Patagonian archipelago during the middle and late Holocene, including increased variability in glacial coverage and marine productivity. Those changes likely impacted the lives of marine hunter gatherers and their exploitation of faunal resources. Here, we examine temporal trends in fishes captu...

On the flanks of >6000 m Andean volcanoes that tower over the Atacama Desert, leaf-eared mice (Phyllotis vaccarum) live at extreme elevations that surpass known vegetation limits. What the mice eat in these barren, hyperarid environments has been the subject of much speculation. According to the arthropod fallout hypothesis, sustenance is provided...

Analysis of stable isotopes in consumers is used commonly to study their ecological and/or environmental niche. There is, however, considerable debate regarding how isotopic values relate to diet and how other sources of variation confound this link, which can undermine the utility. From the analysis of a simple, but general, model of isotopic inco...

Quantifying the tropic position (TP) of an animal species is key to understanding its ecosystem function. While both bulk and compound-specific analyses of stable isotopes are widely used for this purpose, few studies have assessed the consistency between and within such approaches. Champsocephalus gunnari is a specialist teleost that predates almo...

Honey, valued for its nutritional and antimicrobial benefits, has experienced an increased production in recent decades. However, this rise has been accompanied by concerns of adulteration, often involving the fraudulent addition of sugars. Our study sought to compare the physicochemical and isotopic properties of various honeys available to Chilea...

The use of light stable isotope ratios from organic tissues to answer questions relating to physiology, biology, ecology, and archaeology has increased exponentially over the last few decades. The vast majority of studies collect carbon (δ13C) and nitrogen (δ15N) stable isotopes as the ‘default’ isotopes, omitting sulfur (δ34S) due to time, cost, o...

Pinnipeds are considered generalist predators that prey opportunistically on more abundant prey. Thus, their diet could be affected by natural and anthropogenic stressors, such as declines in native prey and increases in exotic prey such as escaped salmon. Using stable isotopes, we evaluated temporal and spatial variability in the diet of southern...

Aquaculture is increasingly important in a growing and hungry world. However, it is also associated with several socio-ecological problems such as non-native fish escaping from aquaculture. A particular issue in Chile is that escaped fish remain the property of the aquaculture operation, resulting in socio-ecological conflict. This article analyzes...

Salmonids were first introduced into the Chilean fresh waters in the 1880s, and c. 140 years later, they are ubiquitous across Chilean rivers, especially in the southern pristine fresh waters. This study examined the brown trout (Salmo trutta) and native taxa ecology in two adjacent but contrasting rivers of Chilean Patagonia. During spring 2016 an...

Chinook salmon represent one of the most successful salmonid introductions in South America, and today multiple naturalized populations exist across Patagonia. Here, we present an updated regional distribution of Chinook salmon that includes new records of occurrences collected between 2006 and 2022. We found a significant range expansion in terms...

Analysis of stable isotopes in cosumbers is used commonly to study their ecological and/or environmental niche. There is, however, considerable debate regarding how isotopic values relate to diet and how other sources of variation confound this link, which can undermine the utility. From the analysis of a simple, but general, model of isotopic inco...

The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large‐scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southe...

Codium fragile is considered one of the most invasive marine seaweeds. It has invaded coastal habitats worldwide in temperate regions (30°–60° in both hemispheres), but it is rarely found at lower latitudes (i.e., tropical and subtropical regions). Here we document the distribution of C. fragile together with relevant size and reproductive paramete...

Because camelids today are found almost exclusively in the South American highlands (puna), archaeologists originally assumed that they largely inhabited that ecosystem in pre-Colonial times (Murra 1972; Núñez 1984; Núñez and Dillehay [1978] 1995). However, we now know that lowland camelid herds were either killed by Spanish conquerors or died from...

Using carbon and nitrogen stable isotope values, we analyzed the trophic position (TP) and the isotopic niche width of lanternfishes from three different areas in the Southern Pacific Ocean. Fishes from Perú had slightly higher δ13C values compared with fish from Chilean areas. In contrast, δ15N values increased with latitude (North to South). Myct...

Limited stocking efforts to introduce Atlantic salmon Salmo salar into Chilean rivers and streams were unsuccessful during the 20 th century. Following the arrival of the aquaculture industry during the 1980s, escaped Atlantic salmon have presented an ecological risk to native taxa through predation, competition, and transmission of pathogens or pa...

El objetivo de este trabajo consiste en establecer si la señal isotópica del carbono y el nitrógeno medida sobre piezas dentales de camélidos modernos de las tierras altas de Atacama refleja las variaciones en la dieta, la movilidad y la territorialidad de estos animales a nivel diacrónico. Se busca explorar el correlato isotópico de la variación e...

Using carbon and nitrogen stable isotope values, we analyzed the trophic position (TP) and the isotopic niche width of lanternfishes from three different fishing grounds in the Southern Pacific Ocean. Fishes from Perú had slightly higher δ13C values compared with fish from Chilean fisheries grounds. In contrast, δ15N values increased with latitude...

Rationale: The analysis of natural variation in light stable isotopes such as carbon (δ13 C), nitrogen (δ15 N) and sulfur (δ34 S) plays an important role in deepening our understanding of ecosystems. To avoid misinterpretation, robust results are required, where pre-treatment steps such as sample homogenization are crucial to guarantee representat...

Stable isotope analysis (SIA) is widely used to assess animal diet and movements, requiring accurate estimates of trophic discrimination factors (TDFs). Since TDFs are only available for a limited number of species, SIA applications typically rely on universal across-taxa averages, disregarding potential sources of variability such as phylogeny, te...

The success of maternal foraging strategies during the rearing period can greatly impact the physiology and survival of dependent offspring. Surprisingly though, little is known on the fitness consequences of foraging strategies during the foetal period. In this study, we characterized variation in maternal foraging strategy throughout pregnancy in...

La Reserva Nacional Katalalixar (RNK) ubicada en la Patagonia Central (48° S), es una de las zonas menos exploradas en Chile que alberga una gran biodiversidad marina, la cual podría ser amenazada debido a la creciente expansión de la industria salmonícola en el área. Por lo tanto, a través del uso de isótopos estables de δ13C, δ15N y δ34S, se estu...

European whitefish is a model species for adaptive radiation of fishes in temperate and subarctic lakes. In northern Europe the most commonly observed morphotypes are a generalist (LSR) morph and a pelagic specialist (DR) morph. The evolution of a pelagic specialist morph is something of an enigma, however, as this region is characterized by long,...

Isotopic techniques have been used to study phenomena in the geological, environmental, and ecological sciences. For example, isotopic values of multiple elements elucidate the pathways energy and nutrients take in the environment. Isoscapes interpolate isotopic values across a geographical surface and are used to study environmental processes in s...

A mechanistic understanding of how environmental change affects trophic ecology of fish at the individual and population level remains elusive. To address this, we conducted a space-for-time approach incorporating environmental gradients (temperature, precipitation and nutrients), lake morphometry (visibility, depth and area), fish communities (ric...

When it comes to the investigation of key ecosystems in the world, we often omit salt from the ecological recipe. In fact, despite occupying almost half of the volume of inland waters and providing crucial services to humanity and nature, inland saline ecosystems are often overlooked in discussions regarding the preservation of global aquatic resou...

We examined how the trophic ecology of nine economically important marine taxa varied across three distinct areas of the Adriatic Sea. These taxa included three species of demersal fishes (European hake Merluccius merluccius, red mullet Mullus barbatus, black-bellied angler Lophius budegassa) and two species of decapod crustaceans (Norway lobster N...

The structure of food webs provides important insight into biodiversity, organic matter (OM) pathways, and ecosystem functioning. Stable isotope analysis (δ13C and δ15N) was used to characterize the trophic structure and the main OM pathways supporting food webs in the Rapa Nui coastal marine ecosystem. The trophic position of consumers and isotopi...

The archaeological record shows that large pre-Inca agricultural systems supported settlements for centuries around the ravines and oases of northern Chile’s hyperarid Atacama Desert. This raises questions about how such productivity was achieved and sustained, and its social implications. Using isotopic data of well-preserved ancient plant remains...

Increasing global concern has been raised about the expansion of hypoxia in coastal waters and its potential to impact benthic ecosystems. Upwelling areas offer opportunities to study the effects of hypoxia on benthic communities under natural conditions. We used a biological trait-based approach and estimated functional diversity indices to assess...

Species diagnosis is essential to assess the level of mislabeling or misnamed seafood products such as sushi. In Chile, sushi typically includes salmon as the main ingredient, but species used are rarely declared on the menu. In order to identify which species are included in the Chilean sushi market, we analyzed 84 individual sushi rolls sold as "...

The widespread importance of variable types of primary production, or energy channels, to consumer communities has become increasingly apparent. However, the mechanisms underlying this “multichannel” feeding remain poorly understood, especially for aquatic ecosystems that pose unique logistical constraints given the diversity of potential energy ch...

Invasive species with migratory behavior and complex life cycles represent a challenge for evaluating natal sites among individuals. Private and government-sponsored initiatives resulted in the successful introduction and naturalization of Chinook salmon (Oncorhynchus tshawytscha) throughout northern and southern Patagonia in South America. Migrato...

Partial migration, where migrant and resident organisms coexist within the same population, has been found in many fishes. Although it seems obvious that different life cycles exploit habitats and food webs differently, few assessments about the trophic consequences of partial migration are available. To unveil part of this complexity, we combined...

This FAO Technical Paper synthesizes current knowledge on the impact of El Niño Southern Oscillation (ENSO) events on fisheries and aquaculture in the context of a changing climate. Fisheries and aquaculture are essential parts of the global food system. The recent discovery that ENSO is far more diverse than previously recognized highlights a pres...

The Cape Horn Biosphere Reserve, one of the last wild areas of the planet, is not exempt from the pressures of global change, such as non‐native species introductions. During 2018 and 2019 we studied the Róbalo river basin in order to update the diversity and distribution of fishes. Here, we report for the first time the native and endangered “Pela...

As biodiversity worldwide is decreasing, to preserve adaptive potential, the importance of maintaining species’ genetic and trait diversities is increasing. An efficient foraging strategy is a critical trait for an organism’s fitness, as it affects its physiology and reproduction. Understanding such strategies is especially relevant for species wit...

Invasive species with migratory behavior and complex life cycle represent a challenge for evaluating natal sites among individuals. Private and government-sponsored initiatives resulted in the successful introduction and naturalization of Chinook salmon (Oncorhynchus tshawytscha) throughout northern and southern Patagonia in South America. These mi...

The trophic ecology of piscivorous Arctic charr (Salvelinus alpinus (L.); charr) in the food webs of large subarctic lakes is not well understood. We assessed charr diets, parasites, growth, maturity, and stable isotope ratios in Fennoscandian subarctic lakes dominated by monomorphic or polymorphic whitefish (Coregonus lavaretus (L.)) populations....

Ambient light and temperature show extreme seasonal variation in subarctic lakes due to the midnight sun period in summer and cold polar night period in winter. These changes have clear impacts on fish feeding and reproduction cycles, potentially affecting the fatty acid ( FA ) composition of muscle. Despite extensive research into fish FA over rec...

Rationale: Stable isotopes of carbon and nitrogen have proved to be valuable tools for researchers working across the different subfields of ecology. However, the chemical pre-treatment of samples prior to analytical determination of stable isotope ratios can influence the results, and therefore conclusions regarding the ecology of the taxon or sy...

Background: Small fishes play fundamental roles in pelagic ecosystems, channelling energy and nutrients from primary producers to higher trophic levels. They support globally important fisheries in eastern boundary current ecosystems like the Humboldt Current System (HCS) of the SE Pacific (Chile and Peru), where fish catches are the highest in th...

Fish – jellyfish interactions are important factors contributing to fish stock success. Jellyfish can compete with fish for food resources, or feed on fish eggs and larvae, which works to reduce survivorship and recruitment of fish species. However, jellyfish also provide habitat and space for developing larval and juvenile fish which use their hos...

Climate change and the intensification of land use practices are causing widespread eutrophication of subarctic lakes. The implications of this rapid change for lake ecosystem function remain poorly understood. To assess how freshwater communities respond to such profound changes in their habitat and resource availability, we conducted a space‐for‐...

Recent studies have shown that anguillid eel populations in habitats spanning the marine–freshwater ecotone can display extreme plasticity in the range of catadromy expressed by individual fish. The apparent use of marine and freshwater habitats by the European eel Anguilla anguilla was examined by analysing the strontium (Sr) and calcium (Ca) conc...

ABSTRACT: Ocean sunfish (Mola spp.) have largely been considered as obligate gelativores, but recent research has suggested that they undergo an unusual life history shift. In this study, analyses of bulk and amino acid nitrogen (δ15N) and carbon (δ13C) stable isotope ratios were employed to provide detailed insight into ontogenetic variation in su...