Abstracts

IAA21 Book of Abstracts (PDF)

Meeting Program/Schedule (PDF)

 

 VIEW MEETING PROGRAM ONLINE

 

 

LIST OF MEETING ABSTRACTS

NOTE: You may quickly navigate to a name you are looking for by clicking a letter below (first letter in their lastname).

Oral | Posters

Oral Presentations

 

 

Day: 3, Session: 3, Talk: 3

The Mineral Content of Cherax quadricarinatus in Souteast Queensland and Northeastern New South Wales

Leyton J. Tierney, Wild CH and Furse JM

The freshwater crayfish Cherax quadricarinatus, is native to northern Queensland, the Northern Territory and southern New Guinea. Within Australia, the species has been translocated from its native habitats in the North to other parts of the Continent, but in particular throughout centraleastern Australia. In southeast Queensland and northeastern New South Wales, a number of feral populations of C. quadricarinatus have established in natural waterbodies and municipal reservoirs. The presence of these large and evidently self-sustaining populations, and the apparent continued spread of the species, has raised concerns about threats these feral populations might pose to other species and ecosystems. While Cherax quadricarinatus is the world’s most intensively studied species of freshwater crayfish, and there is a wealth of information available on aquaculture and physiology of the species, the wild biology and ecology of this species remains very poorly understood. As part of a broader study on the distribution and wild ecology of this species, C. quadricarinatus were collected from waterbodies of various types, with differing underlying substrates and physicochemical characteristics within southeast Queensland and the northeast of New South Wales. These collections permitted analysis of mineral content of 108 C. quadricarinatus from 5 different populations in the study area using the loss-by-ignition method. We will present the results of this study and discuss differences in mineral content between populations. We will also discuss the implications of these results in the context of this species as an aggressive and successful invader of non-native habitats in Australia and elsewhere.

 

 

Day: 4, Session: 2, Talk: 2

The First Evidence of Co-occurrence Between Native Crab and Crayfish in Italy

Elena Tricarico, Cianferoni F, Stasolla G, Inghilesi AF, Zoccola A, Innocenti G and Mazza G

In the Italian freshwater ecosystems, the crab Potamon fluviatile and the white-clawed crayfish Austropotamobius pallipes complex can live in sympatry in some streams, but do not usually occupy the same stream section or pond, suggesting a sharp segregation of the two species. The first instance of the co-occurrence of these two native crustaceans, sharing the same stream area, is here reported for Central Italy. No evidence of agonistic behavioral patterns has been observed. Co-occurrence may be favoured by the crayfish and crabs size, since in the shared area the size of both species is slightly smaller if compared with their size up and downstream, where the species singularly occur. Further observations are needed to better assess the stability of this cohabitation through time.

 

 

Day: 5, Session: 1, Talk: 2

Influence of a Relationship Between Selected Trace Elements and Natural Productivity on Growth and Yield of Marron in a Commercial Farm

Smita S. Tulsankar and Fotedar R

The impact of the relationship among trace elements, natural productivity and the productivity of the aquacultured species is unknown. Data were collected from four marron ponds from an established commercial farm in Manjimup (34.2455°S, 116.1443°E), south-west of Western Australia. Approximately 155 kg of 90-130 g marron/pond were stocked for 12 months. The tri-monthly water samples were collected to investigate the role of 12 pre-selected trace elements viz. manganese, silicon, magnesium, calcium, iron, phosphorus, zinc, selenium, sulphur, copper, aluminium and cobalt on the natural productivity and marron yield. The results showed that phytoplankton density had a strong correlation with aluminium (R2= 0.927) but a weak correlation with iron (0.611). Manganese, magnesium and iron were the only three trace elements showing a strong correlation with zooplankton density. Phytoplankton diversity showed a strong correlation with manganese and iron but weak correlation with aluminium, whereas zooplankton diversity showed a strong correlation with zinc. A strong correlation was observed between wet weights of zooplankton and phytoplankton with aluminium and zinc respectively. Dry weight of zooplankton had a strong correlation with manganese, magnesium, and iron. Wet weight and dry weight of zooplankton showed a significant (P<0.05) correlation with phytoplankton density and diversity. A strong correlation was observed between marron yield at harvest and manganese, magnesium, iron, copper, phytoplankton density and species diversity, and zooplankton density, species diversity and dry weight. In conclusion, trace elements in the marron pond influenced the primary, secondary productivity of the ponds and in turn marron yield.

 

Poster Presentations

 

 

POSTER 3

White-clawed Crayfish (Austropotamobius pallipes) Endangered Species Sampling Methods: Efficiency and Disruptions in the Balance

Olarte N, García-Arberas L and Alvaro A

The distribution of Austropotamobius pallipes in Biscay (Basque Country) is being increasingly restricted. After crayfish plague and the effects of many further threats, this specie is found in small headwater creeks away from the main streams. The species inhabits in small populations, generally isolated and fluctuating number of individuals. The main characteristic of these river stretches with a little flow is that they do not allow trap sampling methodology and so, other methods based on night viewing are used to get data to calculate population estimates. Two small rivers were sampled for 5 years. In this study, we have compared the values obtained by night viewing from river-bank (CPUEs) with manual searching on one pass (CPUEc). We have also correlated these methods with the estimate population size obtained by Removal method (ABUNDANCE). Both indirect estimates were highly correlated with ABUNDANCE, being stronger CPUEs-ABUNDANCE relationship (p=0.80; R2 =0.64) than CPUEc-ABUNDANCE one (p=0.67; R2 = 0.46). Night viewing is an acceptable strategy for population estimates without a direct interaction with the individuals. This strategy may optimize sampling, as it lets increasing the efficiency in effort and time and minimizing the perturbation generated with catching activity.

 

 

POSTER 6

Epifauna on Freshwater Crayfish (Crustacea: Decapoda) in Croatia

Dražina T, Maguire I, Korša A, Špoljar M and Klobučar G

The crustacean exoskeleton is well known substratum for associate species - epibionts. During 2014 and 2015, we have studied epifauna on six different freshwater crayfish species collected from continental and mediterranean regions of Croatia (Europe). Four of them are autochthonous (Astacus astacus, Astacus leptodactylus, Austropotamobius pallipes, Austropotamobius torrentium) and two allochthonous invasive species (Pacifastacus leniusculus and Procambarus fallax f. virginalis). The epibiont samples were collected from the exoskeleton surface and from the crayfish gill cavity. The aims of this research were: (i) to analyse epifaunal assemblage on different freshwater crayfish and (ii) to compare epifauna among different crayfish populations, especially between autochthonous and allochthonous species. A total of 44 different epifaunal taxa were recorded. The most abundant group was Ciliophora, with Vorticella campanula and Epistylis sp. as the most frequent taxa. Rotifera was the most diverse group and 16 different taxa were identified. Four rotifer species (Lepadella astacicola, L. branchiola, L. parasitica and Dicranophorus hauerianus) were determinated as specific inhabitants of certain crayfish species and these rotifers were found exclusively on autochthonous species. Branchiobdellidans were constant crayfish epibionts, and for the first time the North American species Xirogiton victoriensis has been recorded in Croatia. Representatives from Catenulida, Gastrotricha, Nematoda, Bivalvia, Hirudinea, Tardigrada, Crustacea, Hydrachnidia and Chironomidae were also recorded as epibionts on freshwater crayfish. Results of this study suggested the separation of epifaunal assemblage between autochthonous and allochthonous crayfish, as well as the separation of epifauna among autochthonous species. Our results indicate highly diverse, complex and specific epifaunal assemblage on different crayfish populations. Thus, multiple relationships between crayfish host and epibionts will be the topic of further studies.

 

 

POSTER 9

Metabolic Rate of Cambarellus montezumae (Crustacea: Cambaridae): Effects of Size and Seasonal Changes

Latournerié-Cervera JR, García-Padilla GM, and Estrada-Ortega AR

The measurement of metabolic rate is a key element of a species energy balance. The evaluation of respiratory metabolism in natural conditions, allows us to know the energy requirement of the animal for different processes including growth, activity, reproduction, among others. The objective of this study was to know the element (R) of the energy budget equation: C = P+R+F+U (IBP, 1968) in Cambarellus montezumae, during hot rainy season (May – August) and transitional months (September – October) in the area of study. Recently collected samples of crayfish (n=15) representing small, medium and large sizes of both sexes were employed in respirometry experiments, using a closed respirometer. The temperature and water quality were similar to the conditions of the sampling site. Two measurement periods were used: (noon and evening). Average routine metabolic rate was used for comparisons (QO₂: mg O₂/g. dry weight/h) and was converted to cal/g.dw/day using the Q_ox=3.31 cal/mgO₂ (Brafield & Solomon, 1972). Comparisons for size and month were made by ANOVA factorial (3 X 6) and Tukey test post hoc (p<0.05). Significant differences were obtained by month and size. QO₂ was similar between the months of the rainy season, with a temperature average range of (22.3 ± 1.6°C) and had a significant decrease (p<0.05) in October. Relationships of QO₂ – WW were calculated for all months using a potential model. We discuss results in relation to energy requirements of the species for growth and reproduction and its potential use for intensive management.

 

 

POSTER 10

The Impact of Streetlights on an Aquatic Invasive Species: Artificial Light at Night Alters Signal Crayfish Behaviour

Thomas JR, James J, Newman RC, Riley WD, Griffiths SW and Cable J

Artificial light at night (ALAN) can alter the behaviour, communication and orientation of animals, and could interact with other stressors to affect biodiversity. Invasive, non-native species are one of the largest threats to freshwater biodiversity; however, the impact of ALAN on such species is unknown. This study assessed the effects of ALAN at ecologically relevant levels on the behaviour of a globally widespread invasive species, the signal crayfish (Pacifastacus leniusculus). Crayfish were exposed to periods of daylight, control (<0.1 lx) and street-lit nights to test two hypotheses: (1) signal crayfish under natural conditions are nocturnal animals and (2) ALAN reduces the duration of crayfish activity and intraspecific interactions, whilst increasing their propensity to use shelter. Our results confirm that signal crayfish are largely nocturnal, showing peak activity and interaction levels during control nights, whilst taking refuge during daylight hours. However, when exposed to ecologically relevant simulated light pollution from a streetlight at night, activity and interactions with conspecifics were significantly reduced, whilst time spent sheltering increased. Global anthropogenic changes such as ALAN may alter the life history traits and behaviour of invasive species and ultimately influence their impact on invaded ecosystems. The results of the present study suggest that ALAN could reduce the success of signal crayfish in urban areas, by drastically reducing their nocturnal activity. This study is the first to show an impact of ALAN on the behaviour of an invasive, non-native species, and provides information for the management of invasive crayfish in areas where ALAN is prevalent.

 

 

POSTER 13

Some Aspects of the Dynamic Population of a Mexican Crayfish Species, Cambarellus montezumae (Saussure) from Xochimilco

Latournerié-Cervera JR, García-Padilla GM, Estrada-Ortega AR and Arana-Magallón F

At Xochimilco's Lake, still remains a wild population of Cambarellus montezumae crayfish. This population has been declining in the last decades, because of fragmentation and loss of habitat, overexploitation, pollution, competition and predation by alien species. In this study, we analyze dynamic population of this species through indicators of abundance, meristic indexes (wet weight, WW; total length, TL; and cephalothorax length, CTL); frequency of TL distributions, cohort´s growth rate, sex ratio and allometric relationships in crayfishes of both sexes. A total of 1345 C. montezumae crayfish, were collected during a twelve-month sampling, at Xochimilco channels in 2011 annual cycle. W.W. varied between (.01 – 1.53) g, and TL (6.47 – 41.21) mm, significant differences (p<0.05) were found by sex and month. Abundance was higher during hot rainy season (April – August). Significant differences were detected in total sex ratio population (Female:Male) being almost (2:1). Allometric relationships: WW- TL and WW - CTL - were better adjusted by a potential model, and CTL – TL by a linear model. Two cohorts were identified through the annual cycle (the one at April and second in August), and growth rate was calculated for both of them using TL frequency distributions. We discuss dynamic population of this species in relation to habitat changes and anthropogenic disturbances, which have led almost to its collapse and disappearance.

 

 

POSTER 15

Reproductive Cycle of the Marble Crayfish from an Established Population in Croatia

Cvitanić M, Hudina S and Maguire I

The marble crayfish (Procambarus fallax f. virginalis) is a relatively new non-indigenous crayfish species that has established populations in Europe. Until today, it is the only known decapod species with parthenogenetic reproduction. Established population of marble crayfish was recently discovered in a gravel pit in Northwest Croatia. Apart from parthenogenetic reproduction, the invasion success of this species stems from its early maturation, and higher fecundity compared to other crayfish species. Therefore, the aim of this study was to examine the year cycle of the marble crayfish in Croatia, and its potential (number of ovarian eggs) and realized fecundity (number of pleopodal eggs and juveniles). Our results show that all 140 examined individuals were reproductively active during the whole sampling period. Peaks of reproduction activity were recorded from September to November, when both individuals with pleopodal eggs or juveniles as well as individuals with ripe ovarian eggs were recorded. The smallest reproductively active female was 40.81 mm TL, while reproductive output increased with size (TL). The average number of ovarian eggs was 297. The average number of pleopodal eggs was 15% lower than the number of ovarian eggs, while number of juveniles attached to pleopods was reduced by 50% from ovarian egg count. This represents a lower brood loss compared to other crayfish species. Due to almost constant reproduction, early maturation and relatively high potential and realized fecundity in an established population in Croatia, the marble crayfish represents a major threat to the surrounding waterbodies and their native crayfish fauna.

 

 

POSTER 16

Assembly and Annotation of the Marbled Crayfish Genome

Gutekunst J, Falckenhayn C, Gatzmann F, Raddatz G and Lyko F

Marbled crayfish (Procambarus virginalis) are the only freshwater crayfish known to reproduce by cloning (apomictic parthenogenesis). Notably, among genetically identical offspring raised in the same environment distinct phenotypic differences can be observed. These characteristics render the marbled crayfish an interesting laboratory model. A prerequisite for introducing this triploid arthropod as a new model organism and focus of this thesis is the identification of its complete genome sequence. We experimentally determined the genome size at approximately 3.5 Gbp by k-mer analysis and flow cytometry. High coverage sequencing data (~70X) of one individual female was used for a first de novo draft assembly with a length weighted median scaffold size (N50) of 40 kb. Assessing genome completeness using the benchmarking software BUSCO we were able to identify 56% complete and 21% fragmented (out of 2675) conserved single-copy arthropod orthologs. Single nucleotide variations (SNP) analyses of four additionally sequenced individuals from different strains confirmed clonal reproduction and enabled us to describe genomic characteristics such as triploidity and common genotypes. By interspecies comparisons to the closest relative, the sexually reproducing Procambarus fallax, and preliminary automatic genome annotation of about 15,000 protein coding transcripts we found potential alterations in meiosis related genes. These findings provide new insights into mechanisms of parthenogenesis. Genomic data and manual curation services are, after registration, publicly accessible at our Marmorkrebs webserver (http://marmorkrebs.dkfz.de).

 

 

POSTER 17

North American Branchiobdellida (Annelida: Clitellata) or Crayfish Worms in France: The Greatest Diversity of These Alien Ectosymbionts in Europe

Parpet JF and Gelder SR

Over the last five years, biomonitoring of freshwater bodies resulted in alien crayfishes being collected from the Garonne, Loire, Seine and Rhône basins in France. These crayfishes (Pacifastacus leniusculus (Dana, 1852), Procambarus clarkii (Girard, 1952), Orconectes limosus (Rafinesque, 1817)) from North America also carried ectosymbionts of the order Branchiobdellida (Annelida, Clitellata) or crayfish worms. Initially we reported (Gelder et al., 2012) the distribution in France of Xironogiton victoriensis Gelder and Hall, 1990, Cambarincola gracilis Robinson, 1954 and Cambarincola okadai Yamaguchi, 1933 on the signal crayfish, P. leniusculus, indigenous to the Pacific Northwest of North America; additional information is included here. Signal crayfish found in the Seine basin also carried Triannulata magna Goodnight, 1940, and this is the first record of this species in Europe. Louisiana red swamp crayfish, Pr. clarkii, were collected in the Adour basin along with their endemic, Cambarincola mesochoreus Hoffman, 1963. This is the first report of both host and branchiobdellidan in France. A unique host/branchiobdellidan combination was discovered when western North American X. victoriensis was observed on eastern North American spiny cheek crayfish, Orconectes limosus (Rafinesque, 1817). Although France has the most reported alien branchiobdellidan species in Europe, a number of other countries also have established North American branchiobdellidan populations. The impact of these alien species on the endemic Branchiobdella spp. is unknown, but warrants concern and further study, besides investigating their impact on other invertebrates in the freshwater ecosystem.

 

 

POSTER 18

No Species Recognition Between Two Alien Crayfish Species?

Tricarico E, Coignet A and Souty-Grosset C

Crayfish rely on odours for finding a resource, detecting predators and recognizing species. Species that are not co-evolved could not chemically recognize each other. The red swamp crayfish Procambarus clarkii and the spinycheek crayfish Orconectes limosus, both native to North America where they occupy different areas, have coexisted in the “Parc Naturel Régional de la Brenne” (Centre Region, France) since 2007 but in different ponds. Behavioural observations were conducted in October 2014 and April 2015 to assess if P. clarkii and O. limosus are able to chemically recognize individuals of both sexes belonging to the same or other species. In experimental individual aquarium, records of behaviour of 20 Procambarus males and 20 Orconectes males were made of 3-min observation bouts for each of two sequential phases: (a) the “water” phase, following the introduction of 10 mL of well water, (b) the “smell” phase, following the introduction of 10 mL of well water conditioned by (1) P. clarkii male, (2) P. clarkii female, (3) O. limosus male and (4) O. limosus female odour. The time spent by each crayfish in locomotion and other activities (feeding, cleaning), and the time spent in one of three postures (raised, intermediate, or lowered) were recorded every 15 s. Crayfish seem able to recognize the conspecific of the same sex (males), and not the heterospecific, underlying the absence of species recognition in these two species that separately evolved.

 

 

POSTER 20

Novel Microsporidian Infection in the Japanese Endemic Crayfish Cambaroides japonicus

Pretto T, Tanaka, Diéguez-Uribeondo J and Kawai T

The endemic crayfish, Cambaroides japonicus (de Haan, 1841) is the only native crayfish species in Japan. The rapid decreasing of its native range, which comprises Hokkaido and the Northern Honshu, led the Environmental Agency in Japan to consider C. japonicus as an endangered species. During a monitoring survey on the distribution of C. japonicus,/i> in Hokkaido in 2011, a specimen with atypical whitish appearance of the abdominal musculature were observed in Lake Toyoni and porcelain disease (Thelohania sp.) has been suspected. A focused survey conducted in Lake Toyoni in 2013 revealed the presence of macroscopically affected crayfish with a prevalence of 6.3%. Ethanol fixed C. japonicus were analyzed and muscle samples for molecular analysis were taken from 8 affected specimens. The small subunit ribosomal DNA (SSU rDNA), amplified with generic microsporidian primers (Weiss and Vossbrinck, 1998), was sequenced and compared with other marine, freshwater and terrestrial Microsporidia. Histological analysis of the abdomen revealed high densities of ovoid single spores, not contained inside a sporophorous vescicle, in striated muscle cells of the pleonal extensor and flexor muscles. No spores were recorded in the intestinal musculature nor in the ventral ganglia. The affected muscle fibers were frequently surrounded by haemocytic infiltration and sporadic melanization. The phylogenetic analysis of the SSU rDNA placed this undescribed microsporidium between members of the class Marinosporidia (Vossbrinck and Debrunner-Vossbrinck, 2005), distant from the microsporidia of other European and Australian crayfish. Further studies are needed to describe the developmental stages and the ultrastructural features of this microsporidium.

 

 

POSTER 24

Effect of Pharmaceuticals on Crayfish

Shaliutina O and Bláha M

The release of human pharmaceuticals and personal care products into aquatic ecosystems continues to be a serious environmental problem. There is a staggering list of pharmaceuticals that have been detected in surface water, groundwater and tap water. These compounds typically modify the physiology or behavior, of the intended target system, without lethal effect. The wide range of entry points into freshwater systems reaffirms that animals living within those habitats face continuous exposure to pharmaceuticals, even if only at low doses. Crayfish are a crucial invertebrate in freshwater ecosystems. They are omnivorous, and occupy a key position in the trophic web as both predator and prey. With the importance of crayfish to their ecosystems, the introduction of pollutants such as pharmaceuticals, could have negative effects to crayfish populations. For example, pharmaceuticals can cause a mediating aggressive behavior. It has been demonstrated that crayfish injected with serotonin (antidepressant) fights lasted considerably longer. Also, the lasting impact of pharmaceuticals leads to immune system function decline, which greatly increases the mortality rate. Moreover, they can slow down synthesize and release of hormones from the X-organ sinus complex, and thus influence molting, gonad development, water balance, blood glucose, etc. However, despite all data the impact of pharmaceuticals on particular developmental stages, mortality, growth rate and postembryonic development of crayfish had not yet been fully explored. Therefore, we provide an overview about the known effects of pharmaceuticals on crayfish and demonstrate that these effects could be quite multifaceted.

 

 

POSTER 25

Photoperiod Affects Light/Dark Preference and Exploratory Behaviour in Noble Crayfish (Astacus astacus)

Abeel T, Platteaux I, Roelant E, Adriaen J and Vervaecke H

Artificial day-night cycles are known to affect crayfish growth, behaviour and physiological stress levels in aquaculture. Based on the protocol by Fossat et al. (2015), who validated decreased exploratory behaviour and raised photophobia as stress-induced anxiety-like behaviours in Procambarus clarkii, we evaluated the effect of different photoperiods on noble crayfish activity and light/dark preference in an aquatic plus maze. We kept 135 two-summer-old crayfish in a recirculating aquaculture system and exposed them to five different photoperiods: hours light/dark (L:D) 0:24, 8:16, 12:12, 16:8 and 24:0. All animals had access to brushes and PVC pipes as shelters. After 144 days, the crayfish were submitted to the plus maze test. During a ten minute period, each individual’s location was scored every five seconds. Exploratory behaviour was assessed by quantifying the number of movements between different locations in the maze. Light/dark preference was determined by the time spent in the dark or lit arms. A linear mixed model for the different outcomes was fitted using tank as a random intercept and treatment as a fixed effect. Crayfish kept in 24L showed a higher amount of movements (43.6±4.3 mean±stdev) than individuals from all other treatments (ranging from 30.9±2.4 in L16:D8 down to 23.3±3.3 in L12:D12, p=0.0004). They also spent more time in the lit arms of the maze (43.40±1.74%) than animals from the 24D treatment (25.07±4.22%) (p=0.040). These results show that continuous light stimulates exploratory behaviour and continuous darkness causes more neophobia towards lit areas.

 

 

POSTER 28

Management of the Native White-clawed Crayfish, Austropotamobius pallipes, in the Province of Girona

Montserrat J, Macias M and Torres F

The native white-clawed crayfish (Austropotamobius pallipes) was a species commonly found in most watercourses in the basins of the rivers Fluvià, Ter and Muga until the end of the 1970s, when the crayfish plague Aphanomyces astaci arrived, a water mould that led to the disappearance of almost all the populations in these river basins. The white-clawed crayfish populations are currently found in second-order or larger seasonal rivers and fast-flowing streams where, due to some kind of natural barrier (drought in the lower reaches of the watercourse, cliffs, etc.), the fungus was unable to grow. Moreover, during the 1990s, the red swamp crayfish (Procambarus clarkii) population expanded rapidly in the basin and the situation became far worse, since the North American species is both a carrier of the crayfish plague and resistant to this fungal disease. Later, the signal crayfish (Pacifastacus leniusculus) arrived in the Ter River and the spinycheek crayfish (Orconectes limosus) arrived in the Muga River Basin, both species being carriers of the pathogen Aphanomyces astaci. This situation means relict populations of the white-clawed crayfish cannot expand and are forced to survive in the most inaccessible seasonal rivers and fast-flowing streams, facing the danger of a new outbreak of crayfish plague.