Red Swamp Crayfish Procambarus Research Articles

Genetic Diversity Evaluation and Population Structure Analysis of Red Swamp Crayfish (Procambarus clarkii) from Lakes and Rice Fields by SSR Markers

The red swamp crayfish (Procambarus clarkii) is an important aquatic animal and has developed as a popular aquaculture species in China. In this study, a total of 72,839 SSR motifs were identified from transcriptional data, and 20 microsatellite markers of them were finally developed to assess the genetic diversities of seven wild populations from natural lakes and nine cultured populations from rice fields. Genetic diversity was slightly higher in the cultured populations than in the wild populations. The degree of genetic differentiation between cultured populations is slight, while a moderate to a large degree of genetic differentiation between wild populations and most of the variations occurred within individuals (79%). The analysis of cluster, principal coordinate analysis and STRUCTURE were similar, and they showed that isolation-by-distance pattern was not significant. The microsatellite markers developed in this study can not only be used for genetic monitoring of population but also provide important information for the management of breeding and cultured population in red swamp crayfish.

Oxygen consumption in relation to current velocity and morphology in the highly invasive crayfish Procambarus clarkii

The red swamp crayfish (Procambarus clarkii) is the most widely spread freshwater crayfish worldwide. Competing physiological traits can influence invasion success in any given environment by limiting the available scope for aerobically demanding activities. While high flows have been associated with reduced crayfish movement upstream, the effects of flow alteration on their metabolic demands have been largely overlooked. In this study, we estimated routine metabolic rate (RMR) at rest and oxygen consumption rates of crayfish under different current velocities in a flume respirometer, while maximum metabolic rate (MMR) was determined using the exhaustive chase protocol. We also measured some morphometric variables in males and females of crayfish. Oxygen uptake substantially increased with crayfish size and current velocity due to increased energy expenditure to overcome drag and hold a stationary position. Sexual dimorphism in morphological traits did not lead to sexual differences in oxygen uptake. Moreover, we found that individuals operated close to their maximum aerobic capacity at elevated current velocities (≥ 25 cm s−1). This suggested that the high flow-driven energetic demand may compromise the energy available for reproduction, growth and dispersal, thereby affecting overall fitness. These metabolic constraints could partly explain the failed invasions of invasive crayfish in fast-flowing waters.

Determination of the stable isotope discrimination factor of wild organisms: a case study of the red swamp crayfish in integrated rice–crayfish (Procambarus clarkii) culture without artificial diets

ABSTRACT This study collected samples from a 95-day integrated rice–crayfish culture experiment, and determined the stable isotope discrimination factor of the red swamp crayfish (Procambarus clarkii) by using a model method and difference value method. The isotope ratios of P. clarkii and the dietary resources in rice fields and its feeding niche volumes were ‘conservative’ as proposed. This result broadly supported the assumption of the laboratory feeding experiment that animals should be fed a single diet exhibiting a constant isotopic composition. Using standard ellipse areas (SEA) to screen the data, growth- and time-dependent models of carbon and nitrogen isotopes of females and males were obtained. The Δ13C and its half-lives for females and males were 0.67 (21.0 d) and 0.91 (33.0 d), whereas Δ15N and its half-lives for those were 3.45 (17.8 d) and 3.05 (17.3 d), respectively. The results of integrated rice–crayfish culture without artificial diets provides a reference example for future studies on species-specific discrimination factors in specific field habitats.

Unbalanced population structure and reliance on intraspecific predation by largemouth bass in an agricultural pond with no available prey fish

The carnivorous largemouth bass Micropterus salmoides has been introduced to many regions and poses a threat to native aquatic organisms due to predation, resulting in a significant decrease in biodiversity. Under conditions of prey scarcity, the largemouth bass is thought to consume smaller conspecifics. However, little is known about this species’ dietary reliance on intraspecific predation and its impact on the population structure. We investigated the length–frequency distribution of largemouth bass and estimated their reliance on intraspecific predation using stable carbon and nitrogen isotopes in an agricultural pond with no available prey fish. Almost all individual largemouth bass were collected via the pond drainage system. Within the largemouth bass population, the dominant length class was composed of fish measuring 100–160 mm standard length (SL), whereas few individuals measuring < 100 mm SL (first-year juveniles) were collected. The results from a Stable Isotope Analysis in R mixing model indicated that all four length classes (105–146, 165–180, 216–246, and 300–337 mm SL) of largemouth bass fed mainly on juvenile conspecifics and on red swamp crayfish (Procambarus clarkii). First-year juveniles could have been predated by other individuals of various sizes. The dominant 100–160 mm SL length class may have experienced a weak predation pressure when they were in the first-year juvenile class. Consequently, the largemouth bass population was unbalanced, with few first-year juveniles (< 100 mm SL) and dominance of a 100–160 mm SL length class.

Invasive crayfish does not influence spawning microhabitat selection of brown frogs.

Microhabitat selection is a key component of amphibian breeding biology and can be modulated in response to the features of breeding sites and the presence of predators. Despite invasive alien species being among the major threats to amphibians, there is limited information on the role of invasive species in shaping amphibians’ breeding microhabitat choice. The invasive red swamp crayfish (Procambarus clarkii) is a major predator of amphibians’ larvae, including those of the brown frogs Rana dalmatina and Rana latastei. Although qualitative information about the spawning site preferences and breeding microhabitat choice of brown frogs is available in the literature, only a few studies performed quantitative analyses, and the relationship between microhabitat choice and the presence of alien predators has not been investigated yet. The aims of this study were: (1) to characterize the microhabitats selected for clutch deposition by R. dalmatina and R. latastei and (2) to test if the position and the aggregation of egg clutches differ in sites invaded or not invaded by P. clarkii. During spring 2017, we surveyed multiple times 15 breeding sites of both brown frogs in Northern Italy; in each site we assessed the features of the microhabitat where each egg clutch was laid, considering its position (distance from the shore, depth of the water column) and the degree of aggregation of clutches. In each site we also assessed the presence/absence of the invasive crayfish and the relative abundance in the breeding period. We detected egg clutches in all sites; the crayfish occurred in eight ponds. Our results showed substantial differences between the spawning microhabitat features of the two brown frogs: Rana latastei clutches showed a higher degree of aggregation and were associated with deeper areas of the ponds , while Rana dalmatina deposited more spaced out clutches in areas of the ponds that were less deep. For both species, spawning microhabitat features were not significantly different between sites with and without P. clarkii. Although we did not detect behavioural responses to P. clarkii in the choice of spawning microhabitat , additional studies are required to assess whether these frogs modulate other behavioural traits (e.g. during larval development) in response to the invasive predator.

Genetic diversity of Procambarus clarkii populations based on mitochondrial DNA and microsatellite markers in different areas of Guangxi, China

The red swamp crayfish (Procambarus clarkii) is a famous invasive species. However, it has become one of the most important freshwater aquaculture resources in China. Herein, we focus on five artificial cultured populations of P. clarkii in Guangxi, southern China to investigate the genetic diversity based on mitochondrial DNA and microsatellites. The results revealed that the genetic diversity of P. clarkii populations in southern Guangxi (NN and DT) was lower than in central (LZ and LB) and northern (RS) Guangxi. A total of 17 haplotypes were captured from 100 individuals and haplotype 2 mainly existed, and the number of haplotype in NN and DT was less than other populations. The AMOVA showed that genetic variation was determined by within populations. The observed mismatch distribution of overall populations fit the expected distributions, indicating that no obvious demographic expansion, but unimodal was observed in RS, LZ and LB. Fst among most of groups exhibited moderate differentiation. Nevertheless, the gene flow demonstrated there had extensive gene exchanges between different populations, particularly between LZ and LB. UPGMA tree revealed that NN and DT belonged to the same clade, whereas the remaining populations were in the other clade. According to the genetic diversity, there is a need to improve the germplasm resources of P. clarkii in southern Guangxi.

Immunohistochemical localization of a H2S-generating enzyme and its potential molecular target in hepatopancreas of the freshwater crayfish Procambarus clarkii

ABSTRACTThere is increasing evidence showing that the gasotransmitter hydrogen sulfide (H2S) and NF-κB-mediated signaling may play an important role in regulating immune response. However, essentially nothing is known about them in crustaceans, especially the red swamp crayfish (Procambarus clarkii). In this work, we used immunohistochemical method to investigate, for the first time, the presence and distribution of a H2S biosynthetic enzyme (cystathionine β-synthase, CBS) and a member of NF-κB family (RelA/p65) in crayfish hepatopancreas. Results indicated that (1) CBS-like and NF-κB p65-like immunopositive cells coexisted in hepatopancreas; (2) NF-κB p65 was diffusely localized and highly expressed in the cytoplasm of R- and B-cells, but CBS was observed mainly in connective tissue, especially in sinusoids; (3) and normally, at mean optical density (MOD) level, their expression was about 0.0032 ± 0.0028 and 0.0072 ± 0.0039, and proportion (%) of positive cells was 14.37 ± 5.76 and 23.5 ± 14.3, respectively.

Diets of Largemouth Bass (Micropterus salmoides) in the Sacramento San Joaquin Delta

Largemouth Bass (Micropterus salmoides) were introduced into the Sacramento-San Joaquin Delta (the Delta) over 100 years ago. In the last 2 decades, the abundance of centrarchids (including Largemouth Bass) in the littoral zone has increased, while some native fish and fish that were previously abundant in the pelagic zone have declined. Largemouth Bass are now one of the most abundant piscivores in the Delta. Understanding the ecology of this top predator — including a comprehensive understanding of what prey are important in Largemouth Bass diets — is important to understanding how this species may affect the Delta fish community. To address this need, we conducted electrofishing surveys of Largemouth Bass at 33 sites every 2 months from 2008 to 2010, measuring fish fork lengths and collecting stomachs contents at each site. We characterized diets using Percent Index of Relative Importance for 3,004 Largemouth Bass, with samples that spanned all seasons. Amphipods dominated the diets of Largemouth Bass ≤175 mm FL year-round, with dipterans, odonates, and copepods and cladocerans representing other important diet items. Non-native red swamp crayfish (Procambarus clarkii) were the most important prey for Largemouth Bass &gt;175 mm FL. Non-native centrarchids (including Largemouth Bass) and amphipods were important prey items as well. Prickly Sculpin (Cottus asper) were the most frequently consumed native fish. Other native fish and pelagic fish species rarely occurred in Largemouth Bass diets, and we discuss trends in how the frequency of co-occurrence of these fishes with Largemouth Bass in the electrofishing surveys was associated with their frequency in Largemouth Bass diets. The Largemouth Bass in the Delta appear to be sustained largely on a diet of other non-natives that reside in the littoral zone.

Environmental factors influencing the distribution and abundance of the introduced signal crayfish in the north of Iberian Peninsula

The identification of habitat requirements of invasive species is essential to evaluate their spread and to assess the vulnerability of recipient ecosystems. We studied the distribution and abundance of the invasive signal crayfish (Pacifastacus leniusculus) in 43 sites in northern Spain and analysed the relationships with several abiotic and biotic parameters of the aquatic ecosystems. Our results indicated that the abundance of signal crayfish was positively associated with vegetation cover and negatively associated with boulders. Also, its abundance was positively correlated with water temperature, organic matter, cations (e.g. sodium), anions (e.g. sulfates) and abundance of some native fish species (Parachondrostoma miegii and Luciobarbus graellsii). We concluded that the habitat of signal crayfish is among salmonid stretches (headwaters) with cold waters and low proportion of organic debris, and among cyprinid stretches (low waters) with warmer waters which it inhabits with another invasive crayfish, the red swamp crayfish (Procambarus clarkii). Our analysis indicated that the presence of signal crayfish is limited in the uppermost stretches by lower water temperatures and a lower proportion of organic debris. The existence of a natural environmental limiting factor in upstream reaches facilitates the conservation of aquatic ecosystems and native fauna.

Antipredator response of Eurycea nana to a nocturnal and a diurnal predator: avoidance is not affected by circadian cycles of predators

Both predators and prey exhibit cyclic shifts in activity throughout the day, which should cause the threat posed by predators to change in a recurrent pattern. If the threat posed by a predator is dependent on their circadian foraging cycle, prey may respond more or less intensely to predators at different times of day, thereby maximizing the effectiveness and efficiency of avoidance behaviors. We examined whether predator-naïveEurycea nana, a federally threatened neotenic salamander, exhibits a different antipredator response to chemical cues of a diurnal predator, the green sunfish (Lepomis cyanellus), and a nocturnal predator, the red swamp crayfish (Procambarus clarkii). We predicted thatE. nanawould show more intense antipredator responses (reduced activity) to a diurnal predator during the day and to a nocturnal predator at night. We found that, although there was significant antipredator behavior ofE. nanatoward sunfish, there was no detectable response to crayfish and no effect of time of day on responses to either predator, suggesting that eitherE. nanadoes not innately exhibit circadian patterns in avoidance of these species or that those patterns were undetectable in this study. Future studies should examine whether experience with predators may cause these salamanders to be more sensitive to the diel variation in threat, as has been found with some other amphibians and fish. Due to the threatened nature of this species, understanding the factors that influence antipredator behavior are crucial for management.

Antibacterial properties of extracts of Solidago canadensis and their potential use as dietary supplements in red swamp crayfish (Procambarus clarkii)

Canadian goldenrod (Solidago canadensis )i s one of the most destructive invasive weeds in South- eastern China. To evaluate its potential application as dietary supplement in red swamp crayfish (Procambarus clarkii), the antibacterial properties of aqueous and ethanol extracts of this plant against three major pathogenic bacteria in crayfish aquaculture were examined. Inhibition zone tests and determination of minimum inhibitory concentration revealed that the extracts had lower antibacterial activity than extracts from two traditional medicinal plants that possess antibacterial properties, garlic (Allium sativum) and cortex phellodendri (Phello- dendron chinense). However, they did exhibit greater antibacterial effects than extracts from another widely used medicinal plant, Sophora flavescens, and an aquatic weed, Alternanthera philoxeroides. Aqueous extracts of Cana- dian goldenrod gave greater inhibition than the ethanol extracts. Crayfish fed a diet with 2% these aqueous extracts exhibited significantly higher enzyme activity of alkaline phosphatase, catalase and phenoloxidase (P<0.05). Based on the results of this study, we conclude that aqueous extracts of Canadian goldenrod are highly promising for the development of new dietary supplement for use in crayfish aquaculture.

Rapid Evolution of Antipredator Defenses in Frogs

This study examines how coexistence time shapes antipredator responses of the Iberian water frog (Pelophylax perezi) to the invasive red swamp crayfish (Procambarus clarkii). We collected eggs from five frog populations differing in historical exposure to P. clarkii and raised tadpoles in the presence/absence of caged crayfish. Our results suggest that, while naive P. perezi populations responded behaviorally to P. clarkii, the strong predation pressure imposed by the crayfish has induced the evolution of different antipredator defenses in populations with longer coexistence time. These responses suggest that strong selection by invasive predators may drive rapid evolutionary change in invaded communities.

Is the exotic red swamp crayfish (Procambarus clarkii) a current threat for the Mediterranean tree frog (Hyla meridionalis) in the Camargue (Southern France)?

The non-indigenous red swamp crayfish (Procambarus clarkii) has been shown to be a threat for amphibian conservation. Many amphibian species breed in temporary ponds to diminish predation risk as such ecosystems are free of large predators. However P. clarkii, occurring as an invasive species in the Camargue delta, can readily disperse on the ground and thus colonize isolated ponds. We studied the current impact of the exotic crayfish on the reproductive success of the Mediterranean tree frog (Hyla meridionalis). In a mesocosm experiment, we tested the effect of two crayfish densities (1 and 3 crayfish/m2) on tadpole abundance. We also tested in a field experiment, within a temporary pond, the crayfish’s predation on the tree frog’s eggs. Finally, we developed site occupancy models using data from 20 ponds to assess the effect of crayfish abundance on tadpole abundance. Neither the experiments, nor the site occupancy models showed a negative impact of the current crayfish abundance on the tree frog populations breeding in ponds. We found that recorded crayfish densities were lower than in other areas where crayfish has impacted amphibian populations, but we hypothesize that current crayfish abundance in the area may increase in the future, thus impacting tree frog populations.

Shelter Occupancy by Mixed-Species Pairs of Native Signal Crayfish and Non-Native Red Swamp Crayfish Held in Enclosures

ABSTRACT Sheltering ability does not appear to confer an advantage to non-native red swamp crayfish (Procambarus clarkil) in a small, western Washington lake where the invader outnumbers the native signal crayfish (Pacifastacus leniusculus.) When paired with similar-sized non-native P. clarkii, P. leniusculus was adept at monopolizing limited artificial shelter inside enclosures placed on the bottom of Pine Lake. In these contests, the dominant crayfish or winner was typically the one with longer chelae, or, in the case of P. clarkii, the one that was sexually mature. Female crayfishes of both species also were adept at monopolizing the artificial shelter. Furthermore, irrespective of species and sex, when paired with smaller heterospecifics, large crayfish readily monopolized the artificial shelter. These results suggest that additional mechanisms besides shelter competition are contributing to the possible displacement of P. leniusculus in Pine Lake.

Reproductive biology and life cycle of the invasive crayfish Procambarus clarkii (Crustacea: Decapoda) in diverse aquatic habitats of South-Western Spain: Implications for population control

Since its introduction to southern Spain 30 years ago, the red swamp crayfi sh Procambarus clarkii has established stable populations in both natural and man-made water bodies of the Lower Guadalquivir river basin, including the Donana National Park. In order to provide background data for potential management measures, we assessed the fertility, timing of and size at reproduction for this species at 11 sites differing in hydroperiod and habitat characteristics. Fecundity (in terms of the number of eggs per female) was size dependent, with reproduc- tive output per unit of weight being highest in large females from permanent water bodies, especially those from river branches. Size at reproduction was related to water temperature, population density, and the length of the hydroperiod. The smallest mature individuals were found in rice fi eld habitats, which had the highest densities ob- served, were fi lled with water throughout the summer, and had the longest dry period of all the habitats studied (6 months). In rice fi elds, recruitment peaks were observed in early summer and autumn. In permanent water bodies, most recruitment took place in late autumn and spring, whereas in water bodies that dry out in the summer, recruit- ment was mainly in the autumn or early winter. In order to reconcile confl icting interests between economy and ecology in the study area, we propose the transformation of unused rice fi elds, where crayfi sh densities are high, into crayfi sh culture grounds. Creating a hydrological cycle similar to that found in river branches would guarantee their large size at maturity.

Laboratory conditioning to still or flowing water does not affect the responses to a food stimulus by red swamp crayfish (Procambarus clarkii) in flowing water habitats

We tested the role of hydrodynamics in the use of chemical signals by the red swamp crayfish (Procambarus clarkii). We conditioned the crayfish in either a still water or flowing water habitat for 2 weeks. We then observed the crayfish in control (no stimulus) and experimental (food stimulus) trials in one of two flowing water habitats–laminar or turbulent. Habitat use was significantly different between control and experimental observations, but there was no effect of conditioning habitat or experimental habitat on the responses to the food stimulus. This study adds to a growing body of literature consistent with the idea that gross responses to chemical stimuli in crayfish are not affected by the hydrodynamic context in which they are encountered.

Reproductive Habits of Non-native Red Swamp Crayfish (Procambarus clarkii) at Pine Lake, Sammamish, Washington

Reproductive Habits of Non-native Red Swamp Crayfish (Procambarus clarkii) at Pine Lake, Sammamish, Washington

Quality traits of Procambarus clarkii (girard) related to sex and refrigerated storage

The red swamp crayfish (Procambarus clarkii, Girard) is the most widespread alien species in Europe. Imported from Louisiana to southern Spain in 1973, where at present it is reared in crayfish farm and also diffused in the wild, it was introduced into Italy in the ’80s and is now well established in natural environments of northern and central Italy. Naturalization of this alien species poses risks for aquatic ecosystems and its use as food may be a way to limit its spreading. The aim of this study was to analyse the morphological, mercantile and biochemical characteristics of male and female specimens of Procambarus clarkii and to evaluate changes in qualitative traits during refrigerated storage. Specimens of red swamp crayfish collected in a river, after a rearing period of 85 days in tanks, were harvested, killed by hypothermia and refrigerated (1°C). Male (n=31) and female (n=26) specimens were separated and measured for total body and abdomen length, 1 (n=10), 3 (n=16), 8 (n=16) and 10 days (n=15) after harvesting. They were weighed, sectioned to separate claws and tails (shell-on), which were weighed individually and their colour parameters (lightness, L*; chromaticity indexes, a* and b*) measured in dorsal and ventral sites. A pooled sample consisting of tail muscle of 2-3 specimens having the same storage times was homogenized and analysed for total lipids, qualitative and quantitative fatty acid composition and malondialdehyde (MDA). The other tails (shell-on) were steamed, the exoskeleton removed and abdominal muscles (shell-off tails) analysed for colour parameters in dorsal and ventral sites, and for free water (by compression method). Data was analysed by GLM using the SAS Package, with sex, storage time and relative interaction (except for data of chemical analysis) as fixed effects. Females and males differed in total (p<0.05) and abdominal (p<0.01) length (8.65 vs 8.27cm and 4.32 vs 4.04cm, respectively) and in body weight (corrected for cheliped weight, due their lack in some cases; 16.35 vs 13.89g; p<0.05), however the cooked-meat yield of shell-on tails was similar (46.53 vs 42.93%; p=0.19). Regarding colour parameters, the two sexes only differed in L*, which was significantly greater in males in the different sites of measurement, except the ventral site of raw shell-on tails. Males and females showed a similar water holding capacity of abdominal meat (mean 10.78±6.33cm2). No differences between the sexes were recorded for total lipids (mean 1.05±0.14%), MDA content and fatty acid profile (means SFA: 22.16%, MUFA: 28.40%, PUFAn6: 20.39%; PUFAn3: 28.80%; EPA: 18.24%; DHA: 7.17%). During refrigerated storage, a significant decrease in water holding capacity of muscle (free water increasing from 14.07 to 26.15cm2 on days 1 and 10, respectively; p<0.001) and in cooked-meat yield (from 50.92 to 39.11% on days 1 and 10, respectively; p<0.01) and sharp changes in cooked tail muscle colour parameters were noticed. The latter body part showed a significant decrease (p<0.001) in a* and b* at the dorsal site and in L* at the ventral site (77.74 and 49.14 on days 1 and 10, respectively) with increasing storage. During the refrigerated storage of the whole crayfish the changes recorded for the examined parameters indicate the quality decay, particularly after the 3rd day.

Maternal territoriality as an offspring defense strategy in red swamp crayfish (Procambarus clarkii, Girard)

AbstractThe offspring‐defense hypothesis of maternal territoriality in solitary and semisocial mammals [Wolff JO and Peterson JA. 1998. Ethol Ecol Evol 10:227–239] was evaluated in another taxon using maternal and nonmaternal female red swamp crayfish (Procambarus clarkii), a freshwater decapod crustacean that shows pronounced shelter‐related maternal aggression. The maternal females were of three different categories: (1) ovigerous, (2) carrying primarily stage 1 offspring, or (3) tending offspring that were primarily stage 2. Each female was in residence in an individual aquarium containing only a gravel substrate for 24 hr prior to serial intrusions by male conspecifics. Virtually all of the residents, maternal and nonmaternal, excavated a depression (shelter) in the substrate prior to the first intrusion. The results showed that residents in each of the maternal categories won a significantly higher proportion of their encounters than did the nonmaternal residents, which showed only negligible defense and lost every encounter. However, there were no significant differences in encounter outcomes between the maternal resident categories. There was clear defense of the shelter by maternal females, with virtually all fighting being in or around it, thus demonstrating stable, heightened territorial defense throughout these maternal phases of reproduction. This support of the offspring‐defense hypothesis of maternal territoriality is the first such evidence for a freshwater crustacean and is very similar to that recently reported in a related marine decapod, the American lobster (H. americanus). Aggr. Behav. 27:391–403, 2001. © 2001 Wiley‐Liss, Inc.

Bioeconomic Management of Red Swamp Crayfish (Procambarus clarkii) in the Presence of Environmental Externalities

Red swamp crayfish (Procambarus Clarkii) is a valuable renewable resource which creates significant negative externalities to its environment. Crayfish can cause severe crop damage by burrowing in fields and using irrigation systems to spread. These crayfish are resistant to normal dosages of pesticides which are harmful to fish and birds, can endure months of dryness, and live in a low oxygen environment. This paper presents a simple bioeconomic model for optimal use of the red swamp crayfish accounting for its value in consumption, adapting Plourde's (1970) model to include the negative externalities.