Right Whale

SOUTHERN RIGHT WHALE, Eubalaena australis: A long term study of the population dynamics and identification of Marine Protected Areas in Uruguay

Costa P.1, 2; Riet-Sapriza F.G.1, 2; Jorge G.T.1,3 1

Proyecto FRANCAAUSTRAL; 2Cetáceos Uruguay; 3Sección Etología, Facultad de Ciencias, UdelaR.

Conservation Status The Southern right whale (SRW), Eubalaena australis, is considered the rarest of large whales and the population was driven to the edge of extinction during the XVIII and XIX centuries due to the whaling activity (Best & Underhill, 1990; Burnell, 2001). This pressure was too great that by the mid-1840s SRW was considered to be commercially extinct (Stewart & Todd, 2001). Although protected from hunting by international agreement since 1935, the population recovery has been slow (Arias & Harris, 1999; Best et al., 2001; Patenaude & Baker, 2001). However, the SRW is an example of the ability of whale stock to recover from whaling activity increasing at annual rate of 7-8 % (IWC, 2001). The species is currently listed as low risk/ conservation dependant category (IUCN, 2003). This designation implies that southern right whales are showing signs of recovery in some areas, which depends on running conservation programs. If those efforts are interrupted, in a period of five years the species would be changed to the category of threatened species (IUCN, 2003).

Distribution Southern Hemisphere The SRW is a migratory animal, during the austral summer it is found in high latitudes in its subantarctic feeding sites (60º S). At the beginning of the austral winter it 1

migrates to middle and low latitudes, looking for template and calm waters for mating and calving (Payne, 1976; Whitehead et al., 1986; Payne et al., 1990). Courtship, mating and births occur in shallow bays, being these behaviours easily seen from the shore (Payne, 1986). Important breeding areas includes Peninsula Valdés in the South western Atlantic (Payne, 1986; Payne et al., 1990; Bastida & Lichtestein, 1984), South Africa, (Best, 1970, 1981, 1990; Best & Underhill, 1990; Best & Ruther,1992), Tristán da Cunha (Best, 1988), Australia (Bannister, 1990) and New Zealand (Patenaude et al., 1998). Recent research shows that the coasts of Santa Catarina in Brazil are an important breeding and nursing area for SRW (Palazzo & Flores, 1998). Seven feeding grounds are recognised, based on sightings and historical records from commercial hunting (IWC, 2001). One feeding ground extends from Brazil/False to Banks/Malvinas Island in Argentina, considered a corridor offshore Brazil, Uruguay and Argentina, between 30° and 55°S and west of 40°W (IWC, 2001; Tormosov et al., 1998).

Local Uruguay is situated between the grades 30º and 35º South, between two important SRW reproductive sites: the coasts of Santa Catarina State (27º- 25º South, Brazil) and Peninsula Valdés (42º-43º South, Argentina). The geographic location of Uruguay match with other reproductive sites in the southern hemisphere: South Africa (30º-35º S) and The Great Australian Bay (30º-35º S). The main characteristic of this area (30ºS -35ºS) is being a highly complex hydrographic system due to the convergence of waters from different origins: subantarctic waters from Falkland’s currents, subtropical waters from Brazilian currents and fluvial waters from La Plata River. This makes the region highly productive due to the flux of nutrients originated at the run-off of La Plata River and the contribution of subantarctic waters from Falkland’s currents (Gali, 2000). In Uruguay sightings were recorded since the 70’s (Mermoz, 1980), with a maximum of 10 individuals in July of 1975, near the coasts of the islands of Cabo Polonio (Costa et al., 2005). Systematic survey from 2001 to 2003 suggested that of the species was conducted along the Uruguayan coast, to assess the status and habitat Uruguayan coast could be an important social grounds (Costa et al., 2007).

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Southern right whale biology Species Description Reproduction Right whales are slow breeders, females have their first calves around 9 years (Carwardine, 1995; IWC, 2001) and give birth to a single calf every 3 to 5 years (Carwardine, 1995; Kraus & Hatch, 2001). Post-partum ovulation does not appear to occur (Burnell, 2001). The length of gestation is estimated to be between 12 and 13 months (Kraus & Hatch, 2001; Best et al., 2003). Right whales aggregate in large, active groups during which males appear to compete for access to a single female. Interacting groups, which show behavioural events such as tail and flipper slaps, spy hopping and belly up have traditionally been associated with mating groups (Payne, 1986). Hamilton and Mayo (1990), Kraus and Hatch (2001) and Best et al. (2003) defined surface active groups (SAGs) as groups of two or more individuals that interact on the surface, less than one body length apart, in which one focal individual is surrounded by other individuals. The focal animal is usually a mature female surrounded mostly by males (Best et al., 2003). The female often displayed the belly-up event, making copulation difficult and thus inciting males to compete (Cassini & Vila, 1990; Kraus & Hatch, 2001). Males compete at two levels, for access to position next to a female so they can inseminate her, and via sperm competition (Best et al., 2003). Right whales have the largest testes (972kg) and penises (averages 14.3% of their body length) of the baleen whales (Berta & Sumich, 1999; Kraus & Hatch, 2001).

Calf Right whales nurse their calf in template water and protected coast such as bay. At birth calf weight about 3 to 4 tonnes and measure 1/3 to 1/4 of their mother length. The lactation period last one year. Their first migration to the Antarctic occurs when they separate from their mother on their return to breeding and calving sites (Payne, 1986).

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Mother give birth every 3 years and have their first calf on average at the age of 8-9 years ( Payne, 1986).

Diet Planktonic food resources in most habitats where right whales are thought to feed are dominated by the calanoid copepods Calanus finmarchicus, Pseudocalanus sp. and Centropages spp. Although a variety of other food organisms including euphausids, swarming galaethiads and colonial siphonophores have occasionally been reported worldwide (Mayo et al., 2001). Right whales feed by skimming the surface of the water collecting prey on the baleen, as water is expelled by the tongue (Berta & Sumich, 1999). This process requires more energy than the whale would expend by swimming with its mouth closed because of the additional drag. The number of copepods consumed per unit time (and hence the amount of energy available in the form of food) varies with the concentration of copepods in the water. The threshold concentration of copepods estimate below which it is not energetically favourable for the whale to feed is 4 x 103 copepods m-3 (Beardsley et al., 1996).

Conservation & Management Problems and threats A. The numbers of whales present in Uruguay before or during the whaling industry is unknown. Furthermore, the records from 1970’s and 1990’s were occasional and cannot be used to determine population tendencies. For this reason the status of the SRW in our coast is still unknown. The continuity of a long term project like this is important in order to estimate population abundance and rates of population growth. B. There is a gap in the information about the SRW. Research in neighbouring countries (Argentina and Brazil) has been conducted for 35 years and 22 years, respectively. Because of the migration movements of SRW between the Argentinean and Brazilian reproductive sites, and the strategic location of Uruguay (between Argentina and Brazil),

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we hypothesized the existence of a link between the two mentioned SRW reproductive sites in the South-western Atlantic. Furthermore, the role of the Uruguayan coast in the ecology and migratory patterns of the species need to addressed. C. Management and conservation. In 2002, to attract tourism in the winter season, the Uruguayan Government started an ecotourism program (vessel and shore based whalewatching). This program begun without any scientific basis about the impact of ecotourism on SRW. Biological information obtained from this project will be extremely important for the welfare and conservation of the species in Uruguay. The information collected in this project may be used to implement conservation and management plan in Marine Protected Areas, and for conservation activities in the south-western Atlantic.

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Project Description Aims The data generated from this project will be used: a) To determine the status of the population of SRW; b) To identify potential Marine Protected Areas for SRW; c) To establish conservation and management plans for SRW in Uruguay.

Objectives 1. To determine the importance of the Uruguayan coast in the breeding range and migratory route for SRW 2. To study the long term population dynamics (spatial and temporal distribution) of SRW. 3. Create a high-quality of SRW photo-identification catalogue. 4. Compared the Uruguayan SRW photo-identification catalogue with the Brazil’s and Argentina’s SRW photo-identification catalogue. 5. To study the migratory pattern, permanence time of individuals and the relationship between the Uruguayan population and the populations in the region. 6. To study the mating, social and mother-calf behaviour of SRW. 7. To increase local people awareness of the role of SRW in the marine ecosystem and the importance of Marine Protected Areas.

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MATERIAL AND METHODS

Study area: Transect aerial surveys will be performed fortnightly (August to November) and along the coast (250 km) from Punta Ballena (Maldonado Department) to Santa Teresa (Rocha Department), Uruguay.

Study period: From August to November 2007

Aerial sightings: In order to obtain information about the spatial and temporal distribution, and quantitative data of the individuals in the area, aerial surveys will be performed fortnightly during the study period. A one-engine Cessna 172 plane will be used, which has high wings, flight autonomy for 4.5 hours and capacity for 4 passengers including the pilot. The flights will be conducted following the coastline from a distance of 500 meters and at a height of 800 feet, under ideal weather conditions: calm sea, no wind and good visibility. In addition to the number of individuals, geographical position, group composition and behavioural categories will also be recorded.

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Photo-identification: The callosities that are located in different areas on the head of right whales have a general distribution pattern but are highly variable individually. That makes them very useful for the identification of individuals (Payne, 1983). For detecting permanence time and migratory movements it is necessary to create a national catalogue and then make comparisons with the catalogues available in Argentina and Brazil. The photographs will be taken from an airplane at a height of 400 feet, perpendicularly to the head of the whale, especially in the callosity zone (Payne, 1983) and preferentially having the sun behind the photographer. The best moment for doing the taken photos is when the animal emerges for breathing. Photos will be taken with a Nikon D-200 Digital Camera with a Nikon 70-300mm F/4.5-5.6 Lens.

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1. Aerial Survey 1.1. During the period August-November, four aerial surveys were carried out. The dates and composition of the team is shown in Table 1. Table 1. Participants and positions in aircraft during flights. Left ObserverRight Flight No. Date Photographer Observer 1st. 22/08/2007 M. Campodónico R. Álvarez 2nd. 30/09/2007 M. Campodónico P. Laporta 3rd. 08/10/2007 M. Campodónico F.Riet 4th. 23/10/2007 M. Campodónico F.Riet

Annotator F. Riet F. Riet G.T. Jorge G.T. Jorge

Pilot J. Plateiro L. Guichon E. Jackson E. Jackson

1.2. Forty-three was the largest number of individuals observed during an aerial survey and it was on the 23rd of October. Whereas the lowest number of individuals (n=4) observed was on the 22nd of August (Table 2). Two mother-calf pairs were observed twice: on September 30th and on October 23rd. Table 2. Date and number of individuals counted during the flights. Mother-calf Solitary Individuals Date Totals pair individuals in groups 22/08/2007 2 1(2) 4 30/09/2007 2 4 1(3) - 1(4) 31 08/10/2007 3 3(2) - 3(4) 21 23/10/2007 2 8 8(2) - 5(3) 43

1.3. Distributions of individuals and behaviour from August to November. 1.3.1. In the August flight (22nd August) three whales were observed in zone I and one in zone II (Fig. 2). The only group seen was in interaction (Fig. 3).

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August 22nd, 2007 (n=4)

Nº of whales

4 3 2 1 0 I

II

III

IV

Zones

Fig. 2. Distribution of the southern right whales on the 22nd of August, 2007. August 22nd, 2007 (n=1)

Nº of groups

2

I 1

D T

0 1

2

3

4

Group size

Fig. 3. Composition and behavioural categories of group on the 22nd of August, 2007. Behaviour References; I = Interaction, D = Rest, T = Travel.

1.3.2. During the 30th September flight the largest number of individuals were observed in zone IV, the whales were seen in all zones except for zone III (Fig. 4). All groups seen were in Interaction (Fig. 5). Se pte mber 30th, 2007 (n=31)

Nº of whales

20 15 10 5 0 I

II

III

IV

Zones

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Fig. 4. Distribution of the southern right whales on the 30th of September, 2007. Septem ber 30th, 2007 (n=2)

Nº of groups

2

I 1

D T

0 1

2

3

4

Group size

Fig. 5. Composition and behavioural categories of group on the 30th of September, 2007. Behaviour References; I = Interaction, D = Rest, T = Travel.

1.3.3. During the 8th October flight the largest number of individuals were observed in zone IV, and none were observed in zone I and II (Fig. 6). The largest number of groups were seen in Interaction (Fig. 7). October 8th, 2007 (n=21)

Nº of whales

20 15 10 5 0 I

II

III

IV

Zones

Fig. 6. Distribution of the southern right whales on the 8th of October, 2007.

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October 8th, 2007 (n=6)

Nº of groups

4 3 I 2

D T

1 0 1

2

3

4

Group size

Fig. 7. Composition and behavioural categories of group on the 8th of October, 2007. Behaviour References; I = Interaction, D = Rest, T = Travel.

1.3.4. In the second flight of October (23rd October) the largest number of individuals were observed in zone III. The whales were observed in all zones except for zone I (Fig. 8). One group was seen in Rest, six in Interaction and six in Travel (Fig. 9). October 23rd, 2007 (n=43)

Nº of whales

35 30 25 20 15 10 5 0 I

II

III

IV

Zones

Fig. 8. Distribution of the southern right whales on the 23rd of October, 2007.

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October 23rd, 2007 (n=13) 6 Nº of groups

5 4

I

3

D

2

T

1 0 1

2

3

4

Group size

Fig. 9. Composition and behavioural categories of group on the 23rd of October, 2007. Behaviour References; I = Interaction, D = Rest, T = Travel.

3. General Results 3.1. Temporal distribution Southern rights whales were seen every month of the season except for November. Bad weather conditions prevent the realization of the fifth flight. October was the month were more individuals were observed (n=64) (Fig. 10). August-October, 2007 70 Nº of whales

60 50 40 30 20 10 0 Aug

Sep

Oct

Nov

Month

Fig. 10. Number of individuals sighted by month. August-October, 2007.

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3.2. Spatial distribution The largest number of individuals were seen in zone IV (n = 37) followed by zone III (n = 33) (Fig. 11.).

Nº of whales

August-October, 2007 40 35 30 25 20 15 10 5 0 I

II

III

IV

Zones

Fig. 11. Distribution of individuals by zones. August- November, 2007.

3.3. Group composition and Behaviour in respect of group size Groups of two whales were more frequently observed (28.92%), followed by the three (21.69%) and four individuals group size (19.28%) (Fig.12). Of the total sighted unaccompanied whales (n=91), behavioural data is available for 74 individuals. The 51.35% of which were seen in interaction (social behaviour), the 37.84% in travel and the 10.81% in rest. The two individuals group size was the one that involved the largest number of whales (n=24).

August-October, 2007 12 Nº of groups

10 8

I

6

D

4

T

2 0 1

2

3

4

Group size

Fig. 12. Sighting frequency of the different group categories. August – November, 2007. Behaviour References; I = Interaction, D = Rest, T = Travel.

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3.4. Re-identifications in Uruguay 3.4.1. Re-identifications in the same season Five matches were found, which include two mother-calf pairs. The details of the matches are show in tables 4 and 5. Table 4. Unaccompanied rights whale’s re-identifications in the same season. In the same season Details 2003 2005 2007 03/09/2003 22/09/2005 22/08/2007 Photo-id Playa Mansa Playa Mansa Solanas Locality 12/10/2003 11/10/2005 08/10/2007 Rephoto-id La Paloma Laguna Garzón Valizas- Ag. Dulces Locality 41 20 48 Residency (days) 80 30 Movement (km) Table 5. Mother-calf pairs rights whale’s the same season. In the same season Details 2004 14/09/2004 Photo-id La Pedrera Locality 23/09/2004 Rephoto-id Cabo Polonio Locality 10 Residency (days) 30 Movement (km)

re-identifications in

2007 30/09/2007 Laguna Rocha 23/10/2007 La Paloma 24

3.4.2. . Re-identifications between seasons Until now three matches were found. In the three cases the location of the 1st sighting was very close to the location of the re-sighting. The details of the matches are show in the tables 6. Table 6. Unaccompanied rights whale’s re-identifications between the season 2003 and 2005. Between season Details 03/09/2003 12/10/2003 11/10/2005 Photo-id Playa Mansa La Pedrera Calavera-Cabo Polonio Locality 22/09/2005 08/10/2006 08/10/2006 Rephoto-id Punta Ballena Laguna Rocha Lag. Rocha-Garzón Locality

3.4.3. Matching between Uruguay and Argentina There are likely 17 individual matched between Argentinean and Uruguayan catalogue. The analysis is not finished yet, thus the total number of matching between both countries is still unknown.

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DISCUSSION

Temporal distribution Ninety-nine individuals were observed in the 2007 season. This did differs significantly from the number of whales observed in each season from 2001 to 2005 (2001, n=63; 2002, n=44; 2003, n= 51; 2004, n=50; 2005 and n=48) but is similar to the number of whales observed in the 2006 season (n=84). Individuals were seen in all months of the 2007 season except for November (Fig. 10). Whales were more abundant during the period between September-October with a peak in October (Fig. 10). The 2007 season is consistent with the pattern observed in previous years, with more abundance of whales in the period August-October. We suggest that in Uruguay there is a period of abundance that is consistent each year but there is not a peak of abundance, because this, vary year to year. The seasonality (abundance period) observed in Uruguay agrees with what has been observed in Península Valdés, Argentina (Payne, 1986) and Santa Catarina, Brazil (Palazzo & Flores, 1998).

Spatial distribution The zone IV presented the largest number of whales in 2007 (Fig. 8). This did differs from the spatial distribution observed in 2001-2006 seasons, were the zones II and III concentrated the largest numbers of whales. The few matches of whales between seasons (Tables 4 and 5) suggest that for most of the whales, residency in the area does not exceed 30 days. In South Australia, it has been observed that individuals sometimes leave the coastal zone and move to the open sea, which may hinder the determination of residence time for individuals in the area (Burnell and Bryden, 1997). The possibility of something similar happening off Uruguay cannot be ruled out. The variability in the distribution of unaccompanied right whales individuals within and between seasons does not coincide with the behaviors of the mother–calf pair in calving sites such as Península Valdés (Rowntree et al., 2001), Santa Catarina (Palazzo & Flores, 1998), South Africa (Best, 2000), Australia (Bannister, 1990; Burnell, 2001) and New Zealand (Patenaude et al., 1996; Patenaude & Baker, 2001), where mainly females with calves show a preference for certain sites, which are kept for several years.

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Three individuals were re-identified in two different years, for the three whales the location of the 1st sighting was very close to the 2nd sighting, that suggested a high relative philophatry to the area.

Conservation Priorities: Management action. We propose to focus the management actions and conservation efforts towards Zones II, III and IV (Fig 13, areas shaded in red). This area concentrates the largest number of individuals throughout the years (2001-2007). It’s important to continue this study to confirm the short scale distributional tendency and to make statistical conclusion/results more powerful. See Figure 14 for sighting seen in Cerro Verde, proposed Marine Protected Area.

Brasil

Uruguay Argentina

4 3

1

Fig.13. Areas shaded in red are proposed areas to which direct southern right whale management actions and conservation efforts in Uruguay

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Fig 14. Cerro Verde-Uruguayan Atlantic coast: area with the greatest concentration of whales in the year 2007. Coast line = green line; blue dot whales sightings.

Mother-calf pairs Since 2001 mother-calf pairs have been observed between October and November except in 2003 where they were also observed on August and September. Neither 2002 nor 2006 mother calf pairs were seen during the season. During the 2007 season two mother-calf pairs were observed twice, on September and October. One of the calf observed 2007 was half of its mother length, measure that corresponds to the first two or three months of life, according to Thomas & Taber (1984). Meanwhile the other calf observed was less than half of their mother length, measure which corresponds to the first or second months of life (Thomas & Taber, 1984). Since 2001, 80% of the calves observed were half of their mother body length. The two calves observed with less than half their mother body length were seen in the 2001 and 2005 season. This suggest that these calves could have been born in Uruguayan waters. However, evidences show the contrary to our predictions. Most births occur in August (Payne, 1986) and occasionally in October (Whitehead et al., 1986). The duration of the residence of mothers with calves in an area is of about 30 to 70 days; therefore, they are re-sighted several times within the same season (Best, 2000; Rowntree et al.,

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2001). In our study, we only recorded two mother-calf pair duration of residence in 2004 (10 days) and 2007 (24 days). Because most mother-calf pairs were observed only once and considering the calves’ length, we hypothesized that mother do not give birth in our coast. Thus suggested a coastal migration of mother calf pairs from calving grounds further north. Although the migrational pattern of females is still unknown, we suggest that some females do not migrate directly towards their feeding area at higher latitudes, but that they use alternative areas, such as Uruguay, to rest and continue their calving. A possible calving ground could be the Santa Catarina (Brazil) coast, in which a significant number of mother-small calf pairs are usually present (Palazzo & Flores, 1998). Best et al., (1993) found that three mothers identified in South Brazil had been identified in Argentina with different calves in previous years. Our study supports one of the hypotheses proposed by Best et al., (1993) to explain re-identification: some females could move between the two calving grounds in the year their calves are born. A female could give birth in South Brazil and then move south, towards Península Valdés, possibly as a part of a coastal migration towards higher latitudes as the summer arrives (Best, 1970; 1981). A possible alternative is that females migrate north to Uruguay after calving in Peninsula Valdes.

Social Behaviour Most unaccompanied whales were observed in groups of two or more individuals and the 51.35% of which were observed interacting (social behaviour) (Fig. 12). The group size which has the largest number of individuals was two. These results were consistent with the previous year. In all the years, around 75% of the unaccompanied whales were seen in groups of two or more individuals, showing the largest number of individuals involved the groups of two, three and four. This proportion of individuals interacting in a group is higher than the one found in the calving sites of the South-western Atlantic, in which most individuals are females with calves (Burnell & Bryden, 1997; Rowntree et al., 2001). The high proportion of individuals interacting in a group in our coast suggests that Uruguay could be a socializing area compose mainly of adult and/or young individuals. Behaviours comparable to those described for this species such as courting and reproduction have been observed in these groups. It likely that individuals that are not mother-calf pairs, present higher dispersion, shorter duration of residence and lesser fidelity to calving areas than females during calving years. The location where these individuals migrate in winter apart from the calving sites is not. Therefore, to elucidate the behavioural patterns of these individuals will imply a longer term study compared to mother-calf pairs in calving areas. Observations carried out in Rio Grande do Sul State in Brazil show that most individuals were adults and presented copulation behaviours, whereas mother-calf pairs were rarely observed (Palazzo and Flores, 1998). This could indicate that group composition of whales occurring off the Uruguayan coast could be similar to those in Rio

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Grande do Sul. Taking into account that conception and births happening around midwinter (Best et al., 2003; Burnell, 2001; Payne, 1986) and that the behaviours observed in our study are comparable to those of courtship and breeding already described, this further support the idea that the Uruguayan coast could be an area of socialization and breeding for southern right whales. A place exclusively used for reproduction may not exist in the south-western Atlantic. Thus, individuals could reproduce along a corridor, the geographical references of which would be the zones with highest concentrations of females with calves, such as Península Valdés (Argentina) and Santa Catarina (Brazil). Within this, there could be an alternation of individuals between coastal zones and the open sea, as well as feeding events. It is important to continue with photo-identification and with this long-term stud. In the near future we would like to expand the study area further away from the Uruguayan Atlantic coast. The social behaviour and mating strategies of SRW need to addressed and we are aiming to determine biological and/or management stocks by undertaking studies on population genetic structure gene flow between populations from Western South Atlantic. Finally, we suggest to conduct a study to test the hypothesis whether SRW have a feeding habits along the South Western Atlantic.

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Research Priorities Data about spatial (distribution) and temporal (e.g. residence) distribution are crucial for conservation decision-making (1). These information have been collected since 2001 by survey and photo-identification of southern right whale; however to be able to understand the migration pattern, residence and fidelity of individuals between years and estimate abundance, data needs to be collected on a long term basis. Further, the status of the southern right whale in the Uruguay is still unclear. For instance, Uruguay is considered a strategic location because of the movements of this species between the Argentina’s and Brazil’s breeding sites. Preliminary results showed that most individuals were engaged in social activities indicating that Uruguay could be considered as a breeding ground for SRW. Notwithstanding the role of the Uruguayan coast in the distribution, migration and ecology of the species warrants further investigation. Furthermore, the hypotheses that the SRW in Uruguay constitute an isolate stock or that they are related to the populations of Brazil and Argentina should be tested with mDNA genetic variation analysis. If the latter is true, a genetic flow between populations therefore exist, a biological and management stocks in the South-western Atlantic Ocean could be defined. Summary of research priorities: i. Continue with the photo identification program that will allow the application of markrecapture mathematical models to estimate abundance and population parameters. These parameters are extremely important tools for establishing the conservation status of SRW. ii. Deepen in the photo-grammatical identification of categories of whales in Uruguay. This will be a real step forward to determine the role of our coast in the ecology of the species.

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iii. Work on genetic research. This will contribute to understanding of the geographical structure and the regional limits between sub populations of the south-western Atlantic Ocean. Genetic research will be also important in order to understand the relationship between individuals engaged in social groups.

Acknowledgments We are indebt with both Matilde Campodonico the photographer and with Juan Platerio the pilot of Francaaustral Projet and Karumbe Project . We are very grateful to our funding bodies: Cleveland Metro Zoo Park, Cetacean Society International and BP Foundation, without them this project could not have been conducted.

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