Alexnder P. Sukhodolov, Andrei P. Fedotov, Mikhil M. Mkrov,Alin V. Kolesnikov, Ykov A. Sukhodolov, Polin G. Sorokin

aBaikal State University, Irkutsk, Russia

bLimnological Institute of the Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russia

cInstitute of Economic Studies of the Far East Branch of the Russian Academy of Sciences, Khabarovsk, Russia

Q22 C02 R11 Keywords:Baikal Baikal natural territory Baikal omul Maloye more Mathematical modeling

ABSTRACT

1.Introduction

Lake Baikal is a unique creation of nature, the greatest national and world landmark included in the World Heritage List by the UNESCO World Heritage Committee (December 1996).

A special place in the unique fauna of the lake holds Baikal omul, i.e.an endemic of Baikal and a valuable commercial fish species. There are tales and legends about omul and the omul barrel of Baikal. Literary metaphors reflect the attitude to omul not only as a valuable food and delicacy, but as a particular symbol and brand of Baikal.

The acquatorium of Baikal includes several fishing areas with a total area of 3,150,000 ha, where large-scale commercial fishing, having a negative impact on the population of omul, has been carried out since the 19th century (Degtyarev et al., 2008). A task to rebuild the stock of omul was first introduced at the beginning of the 20th century. It became urgent again after the Great Patriotic War (during the war the catch of omul reached its maximum, which led to the depletion of its stock), when it was recommended to put a limit on fishing in Baikal for not less than three years (starting in 1945). It was also recommended to organize a survey of the fishing areas by specialists from the fish farms,impose a ban on net fishing in the spawning season as well as ensure free swimming of fish in the spawning season (Argunova, 2016).

Later, by the end of the 1960s, it became necessary to take emergency measures to preserve the population of Baikal omul, the stock of which had reduced profoundly because of exceeding the catch level by two to three times. The Ministry of Fish Industry of the USSR imposed a several-year ban on fishing for Baikal omul (Order on “Approving fishing regulations …” of 1 December 1969 N°401).At the same time extensive work aimed at increasing productivity of the fishing basins of Baikal, updating the existing fish farms and creating new ones was carried out. At this particular time they built the Barguzin fish farm, the Belsky fish farm, the Chivirkuysky fish farm and the first line of the Selenginsky fish-breeding farm; the Bolsherechensky fish farm, the oldest one in the basin, was reconstructed. These measures contributed to having the stock of omul in Baikal rebuilt.

Recently the problem of depletion of the stock of omul has become urgent again. Its total biomass has reduced from 18,000–20,000 tons in 2008 to 6800–7100 tons in 2017–2018 (Mamontov, 2009; Smirnov et al.2008, 2015, pp. 89–92). Another ban on commercial fishing for omul and limit on recreational or sport fishing were introduced in August 2017. (Order of the Ministry of Agriculture of the Russian Federation of August 29, 2017 N°450 “On introducing changes …”).

How effective is the current prohibitive fishing policy at Baikal? As a result of its implementing together with the reducing of the allowed fish catch the rates of reported fishing have started to decrease. At the same time the rates of illegal, unreported and unregulated fishing are increasing (Tulokhonov, 2018). Using only the prohibitive fishing policy within the Baikal natural territory (BNT) makes the processes of criminalization of this sector increase (Sukhodolov et al., 2020). This is reflected in the fact that the fish catch is concealed and that distorted information is provided; this is classified as violation of the Fishing regulations.

According to the data by the Russian Federal Service for Supervision of Natural Resources, Ministry of the Interior of the Republic of Buryatia,Central Internal Affairs Directorate for the Irkutsk Region and the Administration of the Ministry of Internal Affairs for Transbaikal Region the number of crimes under Art. 256 of the Criminal Code of the Russian Federation committed in the BNT from 2012 to 2018 has increased by 45% (Table 1).

The tendency for the decrease of the number of registered administrative offences when fishing for Baikal omul, which is demonstrated in the second column of Table 1, is unlikely to be connected with the effectiveness of the ban imposed on fishing for omul, if one takes into account the high extent of latency of such crimes and the growth of the amount of confiscated illegal fish catch, which has increased by 6.3 tons(since the ban on fishing for omul was introduced in October 2017).

2.Materials and methods

The article has analyzed criminogenic factors determining wrongdoing and crime in the fishing industry at Lake Baikal applying mathematical tools; a model of the omul population dynamics (taking into account illegal fishing) has been built. The authors have proposed the Maloye More area as a model territory for increasing effectiveness offishing activities in the BNT, where, with the help of hydro-acoustic survey, the Maloye More capacity and prospects for fish farming in this oldest industrial fishing area of Baikal have been assessed in order to use its fish resources for tourism development in this part of Baikal.

Table 1 Dynamics of law violation in the fishing industry in the BNT in 2012–2018.＊.

3.Results

Based on the statistical data for the period of from 2004 to 2018 a multiple regression model is proposed

W

=−1944

,

03+73

,

51

x

+0

,

81

x

+0

,

32

x

, demonstrating the relation between the number of administrative offences

W

and the poverty level

x

, the number of tourists

x

and the total omul catch allowed

x

. It should be noted, that these factors turned out to be the most significant in accordance with Fisher’s criterion, and the model can be used with the determination coefficient

R

=0

,

7.

Taking into account the criminogenic situation related to illegal fishing at Lake Baikal, the authors have proposed the following continuous model of the omul population dynamics (See also (Sukhodolov et al., 2019):):

˙

x

=

ax

+

b

−

cxu

−

dxu

(1−

u

)

,u

∈[0

,

1]

,x

(

t

)=

x

,t

∈[

t

,t

]

.

Here

a,

b

∈

R

are coefficients, characterizing natural increase(decrease) of the omul population without taking into account the fish catch;

c

∈

R

is the efficiency coefficient of the fish catch by player

A

,engaged in reported fishing;

d

∈

R

is the efficiency coefficient of the fish catch by player

B

(engaged in illegal fishing), who, taking into account the amount of fishing by player

A

, also participates in fishing.

x

is the size of the omul population at the start time

t

;

cxu

is the “immediate” fish catch by player

A

;

dxu

(1−

u

)is the “immediate” fish catch by player

B

; a time period [

t

,t

]fixed. The phase variable

x

(

t

)stands for the omul population at a moment of time

t

, and the control variable

u

(

t

)is the amount of the fish catch by player

A

at a moment of time

t

.

In the framework of the model presented and taking into account illegal fishing it is possible to consider some optimal control problems with an integrated objective function (and, probably, limits), describing different goals pursued by those engaged in reported fishing and those ones engaged in illegal fishing. To study these goals one can apply the classical Pontryagin maximum principle, as well as the positional minimum principle (Dykhta & Sorokin, 2019), which is being developed by the Irkutsk school of optimal control.

A good example of practicing measures aimed at increasing the effectiveness of fishing activities in the BNT, while taking into account the growing tourist attractiveness of Baikal, is the Maloye More area that is located between the west coast of Baikal and its biggest Olkhon Island.

The length of Maloye More is 76 km, the width is from the maximum of 17 km to the minimum of 4 km, the depth is 50–100 m, and the surface area is 800 sq m (Kozhov & Misharin, 1943). The oldest Malomorsky fishing area is located right here, it is a historical centre for omul fishing at Baikal. The population of omul is represented by the so-called Selenga population, with a large fish being up to 50 cm long and weighing up to 50 kg, and with an average fish weight being of about 350 g (Bazov, Bazova, 2016).

On the coastal territory of Maloye More, which is assigned to the central zone of the BNT, business activities are limited with the exception of tourism, fishing, agriculture and trade. This being stated, fishing is the oldest specific business activity in this territory, whose development receives a new impulse in connection with the growing tourist attractiveness of this area of Baikal.

The increasing flow of tourists to Maloye More is due to a number of factors. Among them there are picturesque mountain-taiga and steppe landscapes. Maloye More has the longest sun duration on the coast of Baikal, where the sun shines for more than 2200 h a year; this exceeds the sun duration rate for the Gulf of Riga (1840 h a year) and Kislovodsk(about 2000 h a year). Along the coast there are many comfortable bays for holidaymaking and camping as well as shallow bays, where in summer the water temperature rises up to +20C. All this draws holidaymakers to these bays and makes them popular. Among them there is Mukhor Bay with a lot of recreation centres along its coast (The Ministry of Natural Resources and Environment of the Russian Federation,2019).Another important factor is accessibility. The area has a bus and boat transport link with Irkutsk and a ferry transport link with Olkhon Island. The air communication between Irkutsk and Olkhon Island (the village of Kharantsy), which was cancelled in the 1990s, is to be resumed; this will contribute to the tourist attractiveness of this area. All these factors contribute to tourism development in this part of Baikal(Potapova & Sukhodolov, 2019) and the growth of the tourist flow to Baikal (Table 2) and the Maloye More area (Table 3).

The growing tourist attractiveness of the area contributes to developing related economic sectors, with the fishing industry being among them, since the purchase of fish products by numerous tourist centres is increasing, moreover, tourists purchase Baikal omul and take it out of the region as an exotic present from the coast of Baikal.

There is also a necessary eco-economic and historical background to develop the fishing industry in this part of Baikal. Suffice to say, the availability of high-productive supply of fish as well as labour resources available in this territory made it possible to build in 1938 in the central part of Olkhon (in the village of Khuzhir) the Malomorsky fish farm. The farm used powerful freezers for quick freezing of fish; there were large departments for producing salted and smoked fish, they allowed to process more than 2 tons of fish daily, canned fish was also produced there (Table 4) (Sukhodolov et al., 2003).

3.1.Estimation of the local population and tourists demand for omul

For the population of the Olkhon area of the Irkutsk Region, where Maloye More is situated, Baikal omul was traditionally an essential part of the diet. According to the data from the year of 2019 the population of the region was 9500 people. Taking into account the norms of fish products consumption, approved by Order of August 19, 2016 N°614of the Ministry of Health of the Russian Federation on healthy eating, an adult requires annually 22 kg of fish products. The demand for omul for all the inhabitants of the region can be estimated approximately at 105 tons (11 kg per person), on condition that there is a supply of sea fish products in the region and taking into account the sex and age of the population (i.e. children, the aged).

Estimating the demand for omul that comes from the tourists visiting Maloye More it is necessary to take into account two important factors.First of all, the dynamics of the tourist flow growth, which from 2016 to2018 increased by 3.8 times, i.e. up to 530,000 people, with the amount of those ones among them visiting Maloye More growing from 7.2 up to 32.0% (Table 3). The second factor is the multi-year data from the tour operators on food preferences of tourists visiting Baikal. Such tourists prefer, first of all, Baikal omul, its average consumption by a tourist is about 100–150 g a day. Therefore, the total demand for omul, with an average stay for a tourist at Maloye More of 2½ nights and an average tourist flow of 500,000 people, can be estimated at 125 tons. With the growth of the tourist flow this demand can increase up to 200 tons.

Table 2 Dynamics of tourist flow at Baikal (within the Irkutsk Region) in 2016–2018.

Table 3 Dynamics of tourism development in the Maloye More area in 2016–2018.

Table 4 Dynamics of fish production by the Malomorsky fish factory in 1995–2000, tons.

Here it is also necessary to take into account the demand for omul by the staff of the tourist centres and accommodation facilities (in 2018 there were 104 units), such a demand estimates at 0.7–1.2 tons per season.

In such a way, the current and prospective total demand for omul that comes from the local population, hotel staff and tourists in this area can be estimated at 230–305 tons, which is comparable with the marginal fish productivity of the whole Malomorsky fishing area. In regard to this, there is an idea to create facilities for fish farming in the Maloye More area. However, how productive can they be?

4.Discussion

4.1.Eco-economic estimation of the feasibility of building a fish farming facility at Maloye More

An active discussion of the idea of building a fish farming facility at Maloye More began after the introduction of the ban on commercial fishing for Baikal omul in 2017. The Ministry of Agriculture for the Irkutsk Region prepared a fish-breeding and biological feasibility study on building such a facility in the village of Sarma, with the inclusion of the main steps of this initiative in the federal target programme“Protection of Lake Baikal and the socio-economic development of the Baikal natural territory for 2012–2020”.According to the authors of this idea, the fish farm was supposed to compensate for the damage from the illegal fishing at Maloye More for bottom-water and deep-water Sarma omul, as well as Baikal black grayling and Baikal whitefish. According to the press office of the Governor of the Irkutsk Region,Governor Sergey Levchenko discussed this idea in 2019 with Minister of Natural Resources and Ecology of the Russian Federation Dmitry Kobylkin.At the same time a similar idea, however, about building a fish farm in Severobaykalsk, and also with its inclusion in the federal target programme, was proposed by the government of the Republic of Buryatia. How many fish farms should be there at Lake Baikal? How effective are they?

It should be noted, that in the Soviet times five such fish farms were built at Baikal: the Bolsherechensky fish farm, the Selenginskiy fish farm, the Barguzin fish farm and the Chivyrkuysky fish farm in Buryatia,and the Sarma fish farm in the Irkutsk Region. Besides, in the water area of the Irkutsk Reservoir they built the Burduguz fish farm, yet, it was not a fish-breeding farm for Baikal. By now due to socio-economic and technological reasons the Sarma fish farm and the Chivyrkuysky fish farm have been closed down; because of its low productivity the Barguzin fish farm is on the verge of being closed down, as it is not included in any reconstruction programme. A question arises, whether it is worth building a similar fish farm at Maloye More or there is an alternative to this.

Currently, in the Irkutsk Region there are two fish farms, the Belsky fish farm and the Burduguz fish farm. They breed fish and have capacities to breed 10.6 and 0.2 million tons of juvenile omul a year correspondingly. Yet, these fish farms do not release juvenile fish into Baikal.According to our estimation, to purchase juvenile omul just from the Belsky fish farm and transport it to Maloye More (that is 400 km away)will cost a considerable amount of money (Table 5). Meanwhile, both farms can produce not more than 11 million juvenile fish a year (with Maloye More capacity of 23 million juvenile fish a year), which is half of what is required.

To purchase juvenile omul in Buryatia will cost less. However, there are no sufficient production capacities there either to fully provide for the receiving capacity of Maloye More, also, the juvenile fish will have to be transported by road even over a longer distance of 695 km from the Selenginsk experimental fish farm (a branch of the research and production centre of the Vostsib fish farm).

5.Conclusion

According to the statistics, the total commercial omul catch in Maloye More over the years ranged from 100 to 350 tons a year(330,000–1,200,000 fish). The hydro-acoustic survey of the basin of Maloye More conducted in 2007estimated the amount of the commercial omul in the basin at 2 million fish. These data clearly demonstrate that the natural biological capacity of Maloye More is unable to provide for the growing demand for omul that comes from the tourist industry in this area of Baikal. Moreover, with the rapid growth of tourism in this part of Baikal the tourism pressure on the ecosystem and biological resources of Maloye More will be increasing thus hindering natural reproduction of this fish with the risk of depletion of its stock(Sukhodolov, 2010; Sukhodolov & Berezhnykh, 2011).

Table 5 Approximate costs of juvenile fish purchase and transportation.

The possibility of shipping juvenile omul to the basin of Maloye More from several fish farms of the BNT in order to provide for their release into the basin in the quantity required (i.e. 23 million fish) also seems to be of little effect. This is due to the fact, that only 1% of the juvenile fish released into the lake live up to the age of 4–5 years (i.e. 230,000 fish in our case), however, the overpayment related to purchasing the necessary amount of the juvenile fish from the Belsky fish farm only will exceed 300 million rubles.

A fish farm at Maloye More also seems to be of little effect both from the economic and ecological viewpoints. The building of such a fish farm on the coastal territory of 28 ha near the village of Sarma was included in the Programme of complex socio-economic development of the Olkhon area for 2014–2016.The main investor was

Baikal Fish

LLC. The normative time limits for building such a farm were expected to be 5–6 years, the amount of the investment was to be 120 million rubles, the workforce size was supposed to be 25 people. The maintenance of the farm was expected to cost 15–18 million rubles. However, this project was never implemented.

In terms of this, complex and multidisciplinary eco-economic research into assessment of the effectiveness of fish farming at Baikal as well as the usefulness of building fish farms in general and within the basin of Maloye More in particular are becoming very relevant.

CRediT authorship contribution statement

Alexander P. Sukhodolov:

Conceptualization, Writing – original draft, Project administration.

Andrei P. Fedotov:

Conceptualization,Writing – review & editing, Funding acquisition.

Mikhail M. Makarov:

Methodology, Writing – original draft.

Alina V. Kolesnikova:

Writing –original draft.

Yakov A. Sukhodolov:

Writing – original draft.

Polina G. Sorokina:

Methodology, Formal analysis, Writing – original draft.

Acknowledgments

The research is carried out with the support of the Ministry of Science and Higher Education of the Russian Federation, the project title is Ecoeconomic assessment of functioning of freshwater geobiocoenoses,fundamental and applied aspects, the number of state registration is AAAA-A19-119070190033-0, the Ministry of Science and Higher Education of the Russian Federation number is 0279-2019-0003.