BMC Ecology

BMC Ecology 12001,

BioMed Central

Research article
Model-supported estimation of mortality rates in Baltic cod (Gadus morhua callarias L.) larvae: the varying impact of 'critical periods'
Rdiger Voss*1, Hans-Harald Hinrichsen2 and Kai Wieland3
Address: 1Marine Ecology Department, Institute of Marine Sciences Kiel, Dsternbrooker Weg 20, 24105 Kiel, Germany, 2Marine Ecology Department, Institute of Marine Sciences Kiel, Dsternbrooker Weg 20, 24105 Kiel, Germany and 3Greenland Institute of Natural Resources, P.O. Box 570, DK-3900 Nuuk, Greenland E-mail: Rdiger Voss* - rvoss@ifm.uni-kiel.de; Hans-Harald Hinrichsen - hhinrichsen@ifm.uni-kiel.de; Kai Wieland - wieland@natur.gl *Corresponding author
Published: 19 November 2001 BMC Ecology 2001, 1:4 This article is available from: http://www.biomedcentral.com/1472-6785/1/4
Received: 20 September 2001 Accepted: 19 November 2001
2001 Voss et al; licensee BioMed Central Ltd. Verbatim copying and redistribution of this article are permitted in any medium for any non-commercial purpose, provided this notice is preserved along with the article's original URL. For commercial use, contact info@biomedcentral.com

Abstract

Background: Changes in the survival-rate during the larval phase may strongly influence the recruitment level in marine fish species. During the larval phase different 'critical periods' are discussed, e.g. the hatching period and the first-feeding period. No such information was available for the Baltic cod stock, a commercially important stock showing reproduction failure during the last years. We calculated field-based mortality rates for larval Baltic cod during these phases using basin-wide abundance estimates from two consecutive surveys. Survey information was corrected by three dimensional hydrodynamic model runs. Results: The corrections applied for transport were of variable impact, depending on the prevailing circulation patterns. Especially at high wind forcing scenarios, abundance estimates have the potential to be biased without accounting for transport processes. In May 1988 mortality between hatch and first feeding amounted to approximately 20% per day. Mortality rates during the onset of feeding were considerably lower with only 7% per day. In August 1991 the situation was vice versa: Extremely low mortality rates of 0.08% per day were calculated between hatch and first feeding, while the period between the onset of feeding to the state of an established feeder was more critical with mortality rates of 22% per day. Conclusions: Mortality rates during the different proposed 'critical periods' were found to be highly variable. Survival rates of Baltic cod are not only influenced by a single 'critical period', but can be limited at different points during the larval phase, depending on several biotic and abiotic factors.

Background

The eastern Baltic cod (Gadus morhua L.) stock is historically one of the largest in the North Atlantic region [1] with a long-term mean abundance of to tons of spawning stock biomass. The stock is therefore of considerable commercial importance. Due to a
combination of reproduction failure and high fishing mortalities, the stock decreased from >to ~tons from 1982 to 1992, reaching the lowest level on record in 1999 (tons; [2]). Spawning is generally restricted to the deep basins in the Central Baltic Sea (Fig. 1). Due to unfavourable hydrographic conditions in

BMC Ecology 2001, 1:4

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THE BALTIC SEA

cal period' connected to the onset of feeding [11,12], but also the impact of hatching mortality have to be considered. In this approach we use basin-wide abundance estimates from two consecutive surveys to calculate mortality rates. Abundance estimates are corrected for transport processes using the initial horizontal distribution of larvae and applying a 3 dimensional hydrodynamic model. Mortality rates within two periods, from hatch (egg stage IV) to first feeding (larval stage 57) and from onset of feeding to the state of an established feeder (larval stage 8) were calculated. We compared two sampling periods, May 1988 and August 1991. The resulting mortality estimates are discussed with respect to available information on possible sources of mortality, as these are suggesting a high variability in the impact of 'critical periods' on larval survival.

to North Sea

Gotland Basin

Bornholm Basin

Gdansk Deep
Figure 1 The Baltic Sea and its main deep basins. Depth distribution is given by a colour scale.

Results

Initial horizontal distributions The horizontal distribution of cod egg stage IV and larval stage 57 as obtained from the first survey in each field campaign is shown in Figs. 2 and 3. In May 1988 the egg stage IV is concentrated in the area >80 m water depth (Fig. 2a). Especially 3 stations in the north, west and south of the Bornholm Basin showed higher concentrations. In the area outside the 80 m depth contour line only small numbers of cod egg stage IV were found. The distribution of larval stages 57 is a little wider (Fig. 2b), but the highest concentration is still found in the centre of the basin. Only to the east and south-east considerable numbers of larvae were recorded in the area < 80 m depth. During the first survey in August 1991 the centre of the egg stage IV distribution was displaced to the north-western edge of the deep basin (Fig. 3a). The station with the maximum abundance was located just inside the 80 m depth contour line, however, in this region eggs of developmental stage IV were also found shallower than 80 m depth. Figure 3b displays the distribution of the larval stages 57. In contrast to egg stage IV, highest numbers were now obtained in the central part of the deep basin. Considerable concentrations of larvae were also recorded in the area between 6080 m water depth, especially in the north-eastern part of the basin. Hydrodynamic model runs Figure 4 shows the mean circulation (speed, direction and stability) in the depth layers with maximum cod egg or larval abundance for May 1988. The circulation patterns were averaged over a 5 days period, beginning with the time point of the first survey. For the depth layer with the assumed maximum cod egg abundance (6972 m) low transport speeds were found (Fig. 4a). Especially in

Figure 3 August 1991, horizontal distribution of cod early life stages: a) first survey (11 August), cod egg stage IV; b) first survey (11 August), cod larval stages 57; contours of abundance are drawn as n/m2 with dots indicating sampling positions.
the northern part of the basin and along the edges a high stability of the prevailing currents could be recognised. In the centre of the deep basin an almost circular transport regime was established. So, only limited transport rates across the 80 m depth contour line were to be expected. Figure 4b shows the mean circulation for the depth layer of maximum cod larval abundance (3033 m). Also in this case a circular transport regime could be observed. However, the current speed is much higher and the southern edge of the circular transport extends towards shallower regions. The corresponding results for
August 1991 are given in Fig. 5. Compared to May 1988 the current speeds are generally higher. Beside these differences in transport speed, the mean circulation is quite similar for the depth layer of cod eggs (Fig. 5a). The mean circulation relevant for cod larvae (Fig. 5b) looks different: In the area of the deep basin an overall transport towards the north can be observed. Water masses are transported into the basin from the south, while they leave the deep basin in a strong and stable current directed to the north-west (western part of the basin) or towards the east, north-east (eastern part of the basin). In
Figure 4 Mean current fields and stability averaged over 1923 May 1988. a) depth layer 6972 m ; b) depth layer 3033 m. this case larvae found in the central basin during the first survey will have the tendency to be displaced towards shallower regions in the north. Based on the model runs, the development of the relative distribution of cod eggs and larvae to different depth strata (> 80 m and <80 m) was calculated. These data will be used to correct the abundance values found during the second survey in the area > 80 m depth for transport gains or losses. According to the circular transport regime and the rather low current speeds in May 1988 for both, eggs and larvae, only small changes in the relative distribution were found. After 5.66 days (the time interval between the surveys) the transport patterns resulted in net losses of only 6.7 and 3.4 % out of the area > 80 m depth for cod eggs and larvae, respectively. In August 1991 stronger changes in the relative distribution occurred (Fig. 6). Although the circulation patterns in the egg-relevant depth layer were quite similar to those observed in May 1988, the difference in the initial hori-
Figure 5 Mean current fields and stability averaged over 1115 August 1991. a) depth layer 6972 m ; b) depth layer 3033 m. zontal distribution led to a strong net transport out of the area > 80 m depth during the first 50 hours of the model run (Fig. 6). After that, a weaker net transport into the area > 80 m depth occurred. After 5.92 days (interval between surveys) the proportion of eggs distributed inside the area > 80 m depth had almost regained the starting value (61% vs. 58%). For cod larvae in August 1991 a steady transport out of the deep basin can be observed, as expected according to the flow fields. Initially 54% of the larvae were distributed in the deep basin. At the time point of the second survey the proportion has declined to 42%, what means that the abundance found inside the 80 m depth contour line during the second survey will be underestimated by 12%.

Mortality rates For both periods (May 1988 and August 1991) average mortality rates between the oldest egg stage (stage IV) and larval stage 5 (first feeding larvae) as well as between larval stage 57 and larval stage 8 (established feeders)

first survey

second survey

Aug. 1991

cod eggs cod larvae
Figure 6 Proportion of cod eggs and larvae distributed inside the 80 m depth contour line. Temporal evolution due to transport processes in August 1991 (1120 Aug.). Vertical lines indicate the temporal midpoint of sampling.
were calculated. Table 1 shows the daily production values and the corresponding mortality rates with and without correction for transport. Especially for August 1991 the correction for transport had a strong impact. In May 1988 the mortality between egg stage IV and larval stage 5 amounted to ~20% per day. Mortality rates during the onset of feeding (larval stage 57 to larval stage 8) were considerably lower with only 7% per day. In August 1991 the situation was vice versa. There was almost no mortality between hatch and the onset of feeding. Mortality rates of 0.08 % per day have to be regarded as extremely low for cod early life stages. The period to reach larval stage 8, i.e. to survive to the state of an established feeder, was more critical. Average mortality rates amounted to >22% per day. Obviously, during the two time periods investigated, different processes must have acted, limiting survival at different stages of development.
cable for simulating egg and larval drift processes [8,14]. To explicitly test the applicability of the model for predicting the horizontal distribution patterns of ichthyoplankton during the investigated time periods, separate model runs were performed during an earlier study [8]. The simulated results of this study were in good accordance with field observations, confirming the applicability of the Baltic Sea Model. This good accordance could be reached, although, as in the present study, simplistic vertical distribution patterns had to be used. The vertical position of the eggs and larvae does have an influence on their horizontal transport. Unfortunately, no direct measurements for the time periods under investigation are available. While stage-specific vertical distribution patterns of cod eggs are well investigated [6,7,15], corresponding information for cod larvae is rather scarce. The available information on stage-specific vertical distribution of cod larvae in the Baltic [5,16] can only be used to extract rough distribution patterns. If older cod larvae perform diurnal vertical migrations, a s observed in other cod stocks [17] can so far not be answered. As a first approximation of the vertical distribution vertically resolving samplings 4 weeks apart from the periods under investigation were used. It is known that the vertical distribution patterns can change over the spawning period, but strong changes within 4 weeks are not to be expected. Furthermore, a sensitivity analysis conducted for the transport processes in the Bornholm Basin [18] revealed no significant differences in the drift patterns of cod larvae within a vertical range of 12 m. As a conclusion, we are quite confident, that the modelled development of the horizontal distribution patterns are, despite the various shortcomings, close to reality. The importance of corrections for transport processes will even increase for planned studies on sprat larval mortality, as these are distributed shallower in the water column [15,19] and therefore are subject to higher current speeds. There is no indication for a strong small-scale patchiness of cod eggs or larvae, which would not be resolved by the station grid and thereby considerably bias the abundance estimates. As well the results from the 15 years ichthyoplankton time series as results from high-resolution samplers like the Longhurst-Hardy Plankton Recorder (Raab, pers. comm., Inst. Marine Sciences, Kiel) and the Ichthyoplankton Recorder (Mees, pers. comm., Inst. Marine Sciences, Kiel) rather led to the assumption, that the distribution and abundance of ichthyoplankton is well covered by the station grid in use. The uncertainties in the abundance estimates arising from the non-synoptic sampling procedure as well as the spatial sampling resolution can so far not be quantified, but a theoretical study dealing with this problem has been conducted by

Discussion

The applied correction for transport processes had a varying impact. Especially for high speed, non-circular transport regimes these advection processes have to be taken into account, although the principle differences in mortality rates can also be seen without a corresponding correction (see Table 1). It is well known that the flow dynamics in the Baltic Sea are highly complex. They are mainly determined by the ephemeral character of wind stress, the baroclinic mass field and the complicated bottom topography [13]. However, the Baltic Sea Model used for the simulations has generally proven to be appli-
Abundance > 80m depth [%]
Table 1: Cod larval mortality rates:
May 1988 Time interval between surveys: 5.66 days;
August 1991 Time interval between surveys: 5.92 days;

survey

stage age [days] * dt age n/m2obs n/m2/dobs n/m2/dadj M [1/d] M [%/d] n/m2/dcorr M [1/d]corr M [%/d]corr
Egg IV 14.09 5.26 0.98 0.39 0.2359 21.02 0.2226 19.95

L5 19.35 0.21 0.10 0.11

L 57 22.35 6.00 2.43 0.41 0.0804 7.73

L8 28.35 1.50 0.25 0.25

Egg IV 13.51 6.21 0.66 0.27 0.0078 0.78

L5 19.72 0.52 0.26 0.26

L 57 21.72 6.00 1.97 0.33 0.2972 25.71

L8 27.72 0.33 0.06 0.06

0.0729 7.03

0.0008 0.08

0.2547 22.49
*:at mean ambient egg incubation temperatures of 5.75C in May 1998 and 5.87C in August 1991. Observed ( ) and adjusted ( ) abundance (n/ obs adj m2) and daily production (n/m2/d) of different developmental stages inside the 80 m depth contour line, as well as resulting mortaliy rates (M) with and without correction for transport (corr) for May 1988 and August 1991.
Voss and Hinrichsen (in prep.) showing mean errors in abundance estimates of 1020%. Even after accounting for these uncertainties, the results presented here for cod larvae suggest a high variability in the importance of different 'critical periods' for recruitment. In May 1988 the period between hatch and the onset of feeding was characterised by high mortalities (~20 % day-1), whereas during the same period in August 1991 very low mortality rates were observed. Different processes have been proposed to influence survival on this stage. Viable hatch requires a minimum oxygen level of 2 ml/l [20]. To account for year to year variations in the hydrographic environment occupied by the eggs, the so called Reproductive Volume (RV) has been defined [21,22]. The RV defines the volume of water suitable of successful development of cod eggs by threshold levels in temperature (>1.5C), salinity (>11 psu) and oxygen content (> 2 ml/l) as experimental studies have shown that below these limits development of cod eggs ceases before hatch [23,24,20]. In August 1991 the RV in the Bornholm Basin was 127 km3, substantially higher than in May 1988 with only 93 km3. Unfortunately, no field sampling for the vertical distribution of eggs was performed during the two periods, but these results as well as modelling results [4] suggest less favourable hydrographic conditions for the late egg and early larval stages in May 1988. Even if hatching occurs, low oxygen concentrations negatively impact larval activity [25]. Under such circumstances hatched cod larvae might sink to deeper, less oxygenated water layers, as specific gravity increases after hatch and the larvae are not able to counterbalance the sinking

rate. Another potentially important source of mortality is predation by the clupeids s prat and herring. Performed stomach content analysis of sprat and herring indicate considerable predation pressure on all egg stages in May 1988 [26], while for August 1991 the consumption of cod eggs by the clupeids was low [27]. This may have the potential to explain the strong differences in mortality rates during the period from hatch to first feeding encountered in this study. The second investigated 'critical period' ranges from the onset of feeding (larval stage 5) to the state of an established feeder (larval stage 8). During this phase the larvae have to migrate vertically into upper water layers with sufficient light conditions and higher prey concentrations for successful feeding [16]. Predation on these larvae is of less importance, as the vertical overlap between prey and predator is rather limited, with the clupeids feeding within and below the permanent halocline [26,27]. Correspondingly, in May 1988 almost no larvae were identified in the diet of herring and sprat. In a time series principally covering the spawning seasons from 1988 to 1996, only in August 1991 relatively high numbers of cod larvae were found in the stomachs of herring [26], indicating an increased predation pressure. Another possible source of variation in survival are differences in prey availability for the larvae. Unfortunately, there are no data on abundance and distribution of suitable prey organisms, like copepod nauplii and small copepodite stages [2830], for these time periods. The only indication available is that the total meso-zooplankton biomass in the Bornholm Basin was higher in August
1991 than in May 1988 [31]. However, it has been suggested, that prey abundance in the Bornholm Basin is always sufficient to ensure feeding success of cod larvae [32]. Therefore the potential influence of changing prey availability remains to be clarified. The ability of the larvae to migrate vertically and to establish as feeding larvae might be influenced by their energy reserves, i.e. the size and quality of their yolk sac. Egg size is a function of fish size and the batch number spawned [33]. In the beginning and at the end of the spawning season the egg size is smallest. While it was main spawning time in May 1988, August 1991 corresponds to the late spawning season [7]. There are no direct egg diameter measurements available, but due to the relative spawning time egg diameter and therefore yolk reserves should have been higher in May 1988, favouring survival of the larvae. The different mortality rates found for the two investigated periods can not easily be attributed as inter-annual or seasonal differences. Due to the complex abiotic and biotic relationships in the Baltic Sea, it is rather a combination of both effects. However, the two time periods, May 1988 and August 1991 revealed the peak larval abundance in each year, so that changes in mortality rates probably had a comparable impact on the resulting recruitment. Baltic cod recruitment decreased strongly in the beginning of the 1980ies. Since 1985 it fluctuated around a rather low level compared to the late 1970's and early 1980's. Both investigation dates exhibited outstanding high abundance values for cod larvae in the last 15 years [22]. While the spawning stock biomass as well as the potential egg production were higher in 1988 than in 1991 [34], recruitment in 1988 reached only an intermediate level (compared to the 'low recruitment phase' since 1985). The 1991 year-class was above average, but by far also not reaching the values from the beginning of the 1980ies. It becomes obvious that also after reaching the state of an established feeder processes must act as bottlenecks of survival, limiting year-class strength. Besides others, transport processes have been shown to influence survival probability [35,8].

riod', but can be limited at different points during the larval phase, depending on several biotic and abiotic factors. It becomes further obvious that also after reaching the state of an established feeder processes must act as bottlenecks of survival, limiting year-class strength. Field based mortality estimates, as presented here, may help to disentangle the influence of the various stagespecific processes under consideration and to better understand the mechanisms regulating year-class strength.

Materials and Methods

Field data Sampling related to the horizontal distribution and abundance of cod eggs and larvae was performed on 2 consecutive surveys, approximately 6 days apart, in May 1988 and August 1991. These programs constituted the only available surveys from a 15 year period of ichthyoplankton surveys with sampling intervals and larval abundances having the potential for the determination of stage-specific larval mortality rates [22]. The station grid in use comprised 28 and 36 stations in May 1988 and August 1991, respectively, covering the deep part of the Bornholm Basin (water depth >60 m). Data are based on oblique Bongo net tows (335 m and 500 m mesh size). The samples were stored on board in a 4% formaldehyde-seawater solution. In the laboratory the 500 m samples were sorted for cod eggs which were counted and staged. Egg staging was performed according to a 5 stage system based on morphological criteria [36,23], which was adopted for Baltic cod eggs [37,38]. The 335 m samples were sorted for cod larvae, which were counted, staged and measured. Larval staging followed a 10 stage system for Norwegian cod [39]. To check the applicability of this staging system, cod larvae from laboratory studies with known hatching date were sub-sampled daily for a period of two weeks to be able to compare the stage/age relationship (Fig. 7). During cruises in May 1988 and August 1991 no vertical resolving sampling was performed. Therefore we used data from other cruises in the Bornholm Basin to determine the vertical distribution of the eggs and larvae to be incorporated as passive particles into the Baltic Sea Model, i.e. vertical resolving sampling was performed in July 1988 and 1991. In both cases cod eggs concentrated in a narrow depth layer below the halocline, with max imum abundance in 70 m depth [15,4]. Feeding cod larvae (> stage 5) were generally found above the halocline with maximum abundance around 30 m depth [5,16]. This was observed for July 1991 also, while for July 1988, due to very low numbers of larvae caught, no conclusive result could be obtained. Based on these observations the following relative vertical distribution was utilized to implement cod eggs and larvae as additional tracer into the flow fields:

Conclusions

Transport processes have the potential to strongly influence abundance estimates, especially for cod larvae. These processes have therefore to be accounted for when calculating mortality rates. Mortality rates during the different proposed 'critical periods' were found to be highly variable. Survival rates of Baltic cod are not only influenced by a single 'critical pe-
Norwegian cod Baltic cod (5C) Baltic cod (7C)

Mean age [days]

tour line. This was done, as abundance values outside the observation area were unknown and therefore no reliable exchange rates due to transport could be calculated. By restricting the calculations to the area > 80 m depth, reliable exchange rates between the areas 6080 m depth and > 80 m depth could be derived from a hydrodynamic model. The abundance values were then corrected for the amount of transport gains or losses as obtained by the model runs.
Correction of mortality rates by application of a hydrodynamic model As the two surveys were ~6 days apart, changes in abundance due to transport processes had to be taken into account. Therefore, the Bornholm Basin was divided in 3 sub-areas: >80 m, 6080 m and <60 m. While the initial stage specific abundance is known from the survey results for the areas >60 m depth, the abundance for the area <60 m depth was set to be 0. The initial horizontal distributions as obtained by the first surveys were entered into the model as a tracer and the exchange rates between the areas were calculated over time. By this, the abundance found during the second survey in the area > 80 m depth could be corrected for transport gains or losses. The numerical simulations of the Bornholm Basin circulation were performed by application of a three-dimensional (3-D) eddy resolving baroclinic model of the Baltic Sea [13]. The Baltic Sea Model is based on the free surface Bryan-Cox-Semtner model [40] which is a special version of the Cox numerical ocean general circulation model [4143]. The Baltic Sea model comprises the whole Baltic with a horizontal resolution of 5 km and 41 vertical levels specified. For the region of the Bornholm Basin this results in a vertical resolution of 3 m layers. A grid size of 5 km and a time step of 5 min were chosen. Within the Bornholm Basin the model was initialized with three-dimensional hydrographic data (temperature and salinity) obtained during the research surveys. No hydrographic data were taken outside the observational area for running the model and in order to overcome this lack of data, the general features of the Baltic were utilized by incorporation of hydrographic characteristics typical for these regions and time periods obtained from previous model runs. For each depth level of the model, observational data were interpolated onto the model grid by o bjective analysis [44]. The model was forced for all simulations with actual wind data for the entire Baltic provided by the SMHI (Swedish Meteorological and Hydrological Institute). In order to adapt the initial fields to the model dynamics and to the prescribed mass field outside the Bornholm Basin the model was allowed to spinup for 4 days without external forcing prior to incorporation of tracers representing the horizontal distribution of

n = 286

Figure 7 Stage/age relationships of Baltic cod larvae compared to given Norwegian data [37]. Larval age in days after hatch.
- 25% in 2730 m, 50% in 3033 m and 25% in 3336 m for feeding cod larvae (stages > 5) - 25% in 6669 m, 50% in 6972 m and 25% in 7275 m for cod eggs and non-feeding larvae
Estimation of mortality rates Mortality rates were estimated by comparing the daily production of a given developmental stage at the first sampling date with that of a corresponding stage at the second sampling date (cohort method). Temperaturedependent incubation time of eggs were calculated [20] with an estimated ambient mean temperature [4]. As the consecutive surveys were approximately 6 days apart, the developmental stages had to be chosen accordingly. Mean stage-specific ages as well as exact time intervals between successive samplings are given in Tab. 1. As the time interval between the sampling dates did not match exactly the difference in age between developmental stages, the daily production observed at the second sampling date was adjusted [7]. For the young (hatching) larvae mortality rates were calculated from egg stage IV (oldest egg stage) to larval stage L5-7 (first feeding). For the older larvae larval stages 57 were compared with larval stage 8 (established feeding).
While the station grids covered the area > 60 m depth, all calculations were based on the mean abundance (n/m2) of the developmental stages inside the 80 m depth con-
cod eggs and larvae. After this initialization period, the forcing was switched on and the model was run for a period of 10 days. The two periods (1928 May 88 and 1120 Aug 91) exhibit contrasting wind forcing scenarios: In May 1988 wind forcing was relatively low in magnitude and variable in direction. In contrast, the simulation for August 1991 was affected by relatively strong wind forcing of mainly western directions. To visualize the persistent circulation patterns averaged model results for different depth layers in the Bornholm Basin will be presented. However, averaged currents give no information about their variability. Thus, we calculated the stability which is defined as the ratio of the averaged vectorial velocity and the averaged arithmetic velocity.

7. 8. 9. 10.

11. 12. 13. 14. 15. 16.

1 N ui2 + vi2 N i =1

with u =
u and v = N v as the averaged compoN nents of the flow, and N as the number of current observations at the location under consideration. The vectorial mean is obtained from individually observed current vectors, and the arithmetic mean velocity is calculated by averaging the speeds without regard to the current direction [45].

19. 20. 21. 22.

Acknowledgements
We thank Lonny Hansen of the Danish Meteorological Institute for making available the wind data from the weather station at Christians. The work was carried out as part of the BASYS project and of the Baltic STORE project and was funded by a research grant from the European Union (FAIR CT 983959). 24. 25. 26.

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CURRICULUM VITAE

Paul J. Voss
Associate Professor of English Department of English Georgia State University University Plaza Atlanta, GA 30303 Phone: 6158 Fax: 1710 E-mail: pvoss@gsu.edu

Education

Ph.D. M.A. B.A. B.A. English English English Philosophy University of California, Riverside (1995) San Diego State University (1991) College of St. Thomas, St. Paul MN (1986) College of St. Thomas, St. Paul MN (1986)
Teaching and Administrative Experience
Associate Professor of English, GSU Honors Faculty Affiliate, GSU Provost, Holy Spirit College VPAA, Southern Catholic College Director of Undergraduate Studies, GSU Assistant Professor of English, GSU 2001-present 2005-present 2005-present 2000-20002 1999-2002 1995-2001

Publications

BOOKS Loved or Feared: Ethics, Leadership, and the Rejection of Machiavelli (in progress) Elizabethan News Pamphlets: Shakespeare, Spenser, Marlowe, and the Birth of Journalism. Medieval & Renaissance Literary Studies Series (Pittsburgh: Duquesne University Press), 2001. [reviews available in Cithara, Sixteenth Century Journal, Studies in English Literature, Ben Jonson Journal, Spenser Newsletter, Renaissance Quarterly, Huntington Library Quarterly, and other journals] ---Chapter 4: "Marlowe, Shakespeare, Spenser and the Fictive Navarre" reprinted in Elizabethan Drama, ed. Harold Bloom (London: Chelsea House, 2004): 151-91.
ARTICLES "Reading at Risk," Forum: Publication of the Association of Literary Scholars and Critics, ed. Mark Bauerline 2 (Spring 2005): 11-13. ---Republished by the Institute for Effective Governance, Best Articles Series, October 2005. "Printing Conventions and the Early Modern Play, Medieval & Renaissance Drama in England 15 (2003): 98-115. "St. Thomas More: A Family Man for All Seasons," Our Sunday Visitor 91 (30 March 2003): 14. "Dost Thou Think Shakespeare was Catholic?" Our Sunday Visitor 91 (2 February 2003): 14.
"Assurances of Faith: How Catholic Was Shakespeare? How Catholic Were His Plays?" Crisis (July/August 2002): 34-39. Sir Thomas More in the Year of Donnes Birth, John Donne Journal 19 (2001): 1-17. Looking for Martyrs at St. Edmunds College, Envoy 5.2 (2001): 36-41. To Prey or Not to Prey: Prayer and Punning in Hamlet, Hamlet Studies: An International Journal of Research, 23 (July 2001): 59-74. "News Quartos," The Tudor Encyclopedia, ed. Arthur F. Kinney and David Swain (New York: Garland, 2001): 512-13. "Puns and Wordplay in Hamlet," Approaches to Teaching Hamlet, ed. Bernice W. Kliman (New York: MLA, 2001): 231-232. The Catholic Presence in English Renaissance Literature, Ben Jonson Journal 7 (2000): 1-26. John Fowler and Thomas More: The Making of a Saint, 1573, Journal of English and Germanic Philology 94 (October 2000): 492-512. Created Good and Faire: The Fictive Imagination and Sacred Texts in Elizabethan England, Literature and Theology 14 (June 2000): 125-144. "'My Ghostly Father': Teaching the Friar in Romeo and Juliet," Approaches to Teaching Shakespeare's Romeo and Juliet, ed. Maurice Hunt (New York: MLA, 2000): 131-36. Towards a Poetics of the Archive, Introduction co-authored with Marta L. Werner, Studies in the Literary Imagination 32 (Spring 1999): i-viii. Catholic Representation in Early Modern England, The Shakespeare Newsletter 49 (Spring 1999): 18. "Books for Sale: Patronage and Advertising in Late Elizabethan England," Sixteenth Century Journal 23 (October 1998): 733-756. "Debris from Heaven in Paradise Lost," English Language Notes 36 (March 1998): 37-40. "The Faerie Queene 1590-1596: The Case of St. George," Ben Jonson Journal 3 (1996): 59-73. "The Antifraternal Tradition in English Renaissance Drama," Cithara 33 (November 1993): 3-16.
EDITIONS Bibliography and First Line Index of English Verse, 1559-1603, Assistant Director of Research, ed. Steven May (London: Continuum), 2004. Funded by an NEH grant, the Index aims at a complete listing of all verse printed in England during the reign of Elizabeth I (currently numbering over 35,000 poems) by first line, number of lines, author, and subjects. Shakespeares Sonnets. An Online anthology of texts, source material, scholarship, and criticism. The Xanedu Shakespeare LitPack www.xanedu.com. Xanedu is a division of Bell & Howell. Studies in the Literary Imagination, "The Poetics of the Archive," co-edited with Marta Werner, 32:1 (Spring 1999).

BOOK REVIEWS Literature, Nationalism, and Memory in Early Modern England and Wales, by Philip Schwyzer, The Shakespeare Yearbook, forthcoming. Bibliography and First Line Index of English Verse, 1559-1603, ed. Steven W. May and William Ringler, Jr. The Ben Jonson Journal (forthcoming) The Merchant of Venice: New Critical Essays, edited John Mahon and Ellen Macleod Mahon, Christianity and Literature 53 (Summer 2004): 406-08. Shakespeare's Last Plays: Essays in Literature and Politics, ed. Stephen Smith and Travis Curtright, The Ben Jonson Journal 10 (2003): 287-290. The Idolatrous Eye: Iconoclasm & Theater in Early-Modern England, by Michael OConnell,
ACADEMIC AND COMMUNITY SERVICE PRESENTATIONS Discussion Leader, Liberty and Law in Three Shakespearean Comedies, Liberty Fund Colloquium, Seattle, WA, December 8-11, 2005. Session Chair, Texts and Paratexts in Early Modern England, SAMLA, Atlanta, GA, 6 November 2005. Session Chair, Religion on Stage/Page in Renaissance England, SAMLA, Atlanta, GA, 5 November 2005. Keynote Address: Thomas More and the Ideal of Servant Leadership, Florida Medical Association Annual Lecture, Pensacola, FL, 9 October 2005. Seminar Leader, Revenge Tragedy and Civic Responsibility, Montreal Canada, October 20-23, 2005. Servant Leadership and Virgils The Aeneid Holy Spirit College, 8 September, 2005. Loved or Feared: Leadership, Ethics, and the Rejection of Machiavelli, HSCC Mens Club, 12 September 2005. Leadership and the Epic Hero, Sweet Briar Alumnae Association, January-February, 2005. "Dear Mr. Spenser: A Catholic Response to The Faerie Queene, 1596," Shakespeare Association of America Annual Conference, Bermuda, 18 March 2005. Why Ethics Matters: Leadership and Philosophy, Nineteenth-Century History Group, Atlanta History Center, 6 January 2005. Seminar Leader, "Liberty and Education in Newman's Idea of a University" San Antonio, TX, 11-14 March 2004. "St Thomas More: A Man for All Seasons Indeed," Thomas More Society, Atlanta, GA 22, June 2004. "The Four Loves of C. S. Lewis," An Evening with C. S. Lewis, Atlanta, GA, 4 May 2004. "A Southern Catholic Moment," Faith and Reason Conference, Atlanta GA, 12 November 2002. "The Literary Imagination from Plato to John Paul II," Prince of Liechtenstein Fellowship, Kalwang, Austria, 13 June 2002. Commencement Address Speaker: "The Liberal Arts and the Life of the Mind," Aquinas College, Nashville, TN, 10 May 2002. "Is That A Catholic Book You're Reading?" Renaissance Society of America, Phoenix AZ, 12 April 2002. "Using the Sonnets to Teach Critical Thinking," Conversations at GSU, Atlanta GA, 9 February 2002. "Shakespeare's Radical Catholicism," Ave Maria University, Ypsilanti MI, 14 March 2001. "Acrostic Verse and the Ordering of Knowledge" Hudson Strode Annual Lecture, University of Alabama, 3 March 2001.

Elizabethan Acrostic Verse, Sixteenth Century Studies Conference, Cleveland OH, 5 November 2000. Session Chair: Constructing Truth, Sixteenth Century Studies Conference, Cleveland OH, 4 November 2000. Shakespeare and the Four Loves, Prince of Liechtenstein Fellowship, Sonntagberg Austria, 12 June 2000. Sir Thomas More at Donnes Birth, Donne Returns to Loseley, Surrey, England, 18 May 2000. Convention and Anti-Convention in Much Ado About Nothing, St. Edmunds College, Ware England, 15 May 2000. Bibliographic and Linguistic Codes in Printed Plays, Shakespeare Association of America, Montreal Canada, 8 April 2000. Seminar Leader: Catholic Representation in Early Modern England, Shakespeare Association of America, San Francisco CA, 1 April 1999. Created Good and Faire: Two Elizabethan Bible Poems, Sixteenth Century Studies Conference, Toronto Canada 25 October 1998. Audience Reception and the Elizabethan Printed Play, Southeastern Renaissance Conference, Chapel Hill NC, 18 April 1998. Printing Conventions and the Early Modern Play, Shakespeare Association of America, Cleveland OH, 19 March 1998. "Navarre Before and After: The Massacre at Paris and Oath-Breaking," Modern Language Association Convention, Toronto Canada, 30 December 1997. "Good News From France: English Serial Publication, 1590," Southern Conference on British Studies, 6 November 1997. "John Fowler and Thomas More: The Making of a Saint, 1573," Sixteenth Century Studies Conference, Atlanta GA, 25 October 1997. Session Chair: "The 16th-Century British Archive in the 21st Century," Sixteenth Century Studies Conference, Atlanta GA, 24 October 1997. "The Place of The Massacre at Paris in Marlowe's Canon," Shakespeare Association of America, Washington D. C., 27 March 1997. "Dead Poets and Forgotten Verse, 1559-1603," Sixteenth Century Conference, St. Louis MO, 24 October 1996. "Early English Serials and Periodic Publication, 1589-1593," Georgia State University Print Culture Lecture Series, 19 January 1996. "Polixenes as New Historicist: The Winter's Tale and Spiritual Catharsis," Western Regional Conference on Christianity and Literature, Santa Clara University, 6 May 1995. "The Political Geography of France in Marlowe and Shakespeare," Shakespeare Association of America, Chicago IL, 25 March 1995.
"The Unfortunate Theater of France: Shakespeare, Marlowe, and the Elizabethan News Quarto," Georgia State University, 20 January 1995. "Teaching Shakespeare to Undergraduates," Utah State University, 10 January 1995. "Kissing Cousins: Elizabethan News Quartos and English Renaissance Drama 1589-93," Southwest Regional Renaissance Conference, San Marino, CA 13 May 1994. "New Historicism and the Secular Ethic," Shakespeare Association of America, Albuquerque NM, 15 April 1994. "Friars in Literature and the Shakespearean Variant," Renaissance Conference of Southern California, Huntington Library, 6 March 1993. COURSES TAUGHT English 435: English 436: English 836: English 837: English 806: English 410: English 810: English 430: English 830: English 431: English 439: English 201: Shakespeare's Tragedies Shakespeare's Comedies and Romances Shakespeare's Tragedies (Graduate) Shakespeare's Comedies (Graduate) Literary Theory (Graduate) Elizabethan/Jacobean Drama Elizabethan/Jacobean Drama (Graduate) Renaissance Literature I Renaissance Literature I (Graduate) Renaissance Literature II Milton World Literature

HONORS, AWARDS, and ACTIVITIES Nominated for GSU Distinguished Honors Professor (1997, 2002, 2003, 2004) Dr. Laurence Korn Fellowship (2005) [$10,000] Earhart Fellowship (2004) [$13,200] Laurence Korn Fellowship (2004) [$10,000] GSU Summer Research Grant (2004) [$7500] GSU Summer Research Grant (2000) [$7500] Archive Travel Grant (2000) [$1000] FLC Initiative Grant (1999, 2000) [$5000] Nominated for Outstanding GSU Faculty Member (1999) Nominated for GSU Outstanding Junior Faculty (1998) Liberty Fund Participant (1998-2005) Liberty Fund Conference Director (2002-2005) GSU Summer Research Grant (1998) [$7500] NEH/Dr. Larry Korn Research Grant (1995,1996) [$2500] ALSC Travel Award (1995,1996) Collegium Summer Institute Fellowship (1995) UCR Graduate Fellowship (1995) [$1000] Kathryn Whitten Scholars Award (1990-1991) [$3500]
PROFESSIONAL ORGANIZATIONS
Shakespeare Association of America Association of Literary Scholars and Critics Fellowship of Catholic Scholars John Donne Society Milton Society Marlowe Society of America Chesterton Society Huntington Library Reader British Library Reader Cambridge University Library Reader