TEST DEVICE FOR NONINVASIVE TESTING OF FISH HABITAT SELECTION AND APPLICATION THEREOF

Abstract

A test device for noninvasive testing of fish habitat selection and application thereof is described herein. The device includes a camera device, a water circulating system, a fish transporting barrel, and a test water tank. The fish transporting barrel is a water barrel with an openable bottom. The central area of the test water tank is arranged as a closed adaptation area, a water outlet is formed in the bottom of the adaptation area. Fish passages are formed in the adaptation area. Test areas with equal sizes are formed around the adaptation area through partition plates. A water inlet is formed in each test area. Water flow buffering plates are arranged corresponding to the water inlets. Fish passages are formed in the bottoms of the partition plates of the test areas. The water inlets of the test areas are connected to the water circulating system.

Claims

1. A test device for noninvasive testing of fish preference, comprising: a camera device; a water circulating system; a fish transporting barrel; and a test water tank; wherein: the fish transporting barrel is a water barrel with an openable bottom, the bottom of the fish transporting barrel is connected to a traction device, the test water tank is a container with an opening in top, and the central area of the test water tank is arranged as a closed adaptation area through partition plates; a diameter of the adaptation area is greater than a diameter of the fish transporting barrel; a water outlet is formed in the bottom of the adaptation area; fish passages are formed in positions, close to the bottom of the partition plate, of the adaptation area; test areas with equal sizes are formed around the adaptation area through partition plates; a water inlet is formed in a wall of the water tank where each test area is located; water flow buffering plates are arranged corresponding to the water inlets; fish passages are formed in the bottoms of the partition plates of the test areas; the water inlets of the test areas are connected to inlet water of the water circulating system after being connected in parallel through water pipes; another end of the water circulating system is connected to a water outlet; the camera device is arranged at an upper part of the test water tank; and the water circulating system comprises a filtering system and a circulating pump.

2. The test device of claim 1, wherein the traction device is a pull rope or a pull rod.

3. The test device of claim 1, further comprising a retractable grille.

4. The test device of claim 1, wherein the camera device is an infrared camera device.

5. The test device of claim 1, wherein the partition plates are light tight partition plates.

6. The test device of claim 1, wherein a handle is arranged on the fish transporting barrel.

7. The device of claim 1, wherein substrate layers are paved at the bottoms of the test areas.

8. The test device of claim 1, wherein light sources are arranged in the test areas.

9. A method for noninvasive testing of fish preference in detection of light preference, substrate preference, or the influence of water flow velocity of fish utilizing the test device of claim 1, the method comprising: filling the test water tank with water; providing one or more fish in the water tank; and observing and recording positions of the one or more fish in the water tank utilizing the camera device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG. 1 is a schematic structural diagram of a test device for noninvasive testing of fish preference in Embodiment 1 of the present disclosure;

[0035] FIG. 2 is a vertical view of the test device for noninvasive testing of fish preference in Embodiment 1 of the present disclosure.

[0036] In the drawings: 1—test water tank, 2—fish transporting barrel; 2-1—pull rope; 2-2—handle; 2-3—bottom of water barrel; 3—retractable grille; 4—adaptation area; 5—partition plate; 6—fish passage; 7—water inlet; 8—water flow buffering plate; 9—water circulating system; arrow-water flow direction.

DETAILED DESCRIPTION

[0037] The technical solutions of the present disclosure, if not specified, are all conventional solutions in the art; the reagents or materials, if not specified, are from commercial channels.

Embodiment 1

[0038] A test device for noninvasive testing of fish preference includes a camera device, a water circulating system 9, a fish transporting barrel 2, a test water tank 1, and a retractable grille 3.

[0039] The fish transporting barrel 2 is a cylindrical water barrel with an openable bottom. The bottom of the water barrel is evenly divided into four parts by passing through the center of the circle. The periphery of the bottom is movably linked with the bottom of the wall of the water barrel. Pull ropes 2-1 are arranged bottom 2-3 which is divided into four parts. A handle 2-2 is arranged on the fish transporting barrel.

[0040] The test water tank 1 is a round container with an opening in top. The central area of the round container is arranged as a closed circular adaptation area 4 through partition plates. The diameter of the adaptation area 4 is slightly greater than that of the fish transporting barrel 2. A water outlet is formed in the bottom of the adaptation area. Fish passages 6 are formed in the positions, close to the bottoms of the partition plates, of the adaptation area. Test areas with equal sizes are formed around the adaptation area through partition plates 5. A water inlet 7 is formed in the wall of the water tank where each test area is located. Water flow buffering plates 8 are arranged corresponding to the water inlets. Fish passages 6 are formed in the bottoms of the partition plates 5 of the test areas.

[0041] The water inlets 7 of the test areas are connected to inlet water of a water circulating system 9 after being connected in parallel through water pipes. The other end of the water circulating system is connected to a water outlet.

[0042] The camera device is arranged at the upper part of the test water tank 1. The camera device is an infrared camera device.

[0043] The water circulating system 9 includes a filtering system (Sensen CPA 5000) and a circulating pump (WTP horizontal high-efficiency energy-saving special circulating pump 40-125-1.1).

[0044] The partition plates are light tight partition plates.

Embodiment 2

[0045] Application of a test device for noninvasive testing of fish preference in light preference test of schizothoracids:

[0046] 1. The test water tank in the device of Embodiment 1 was filled with water, the water inlet amount and the water outlet amount were regulated through the water circulating system, different colors of light strips (white light, green light, red light, and blue light) were arranged in the test areas, and the light intensity was regulated (white light: 62.22±14.98 lx, green light: 62.11±10.87 lx, red light: 51.11±12.15 lx, blue light: 63.55±25.97 lx) to create required environments.

[0047] 2. Fish preference test: one test fish was placed into the fish transporting barrel to adapt for 30 minutes, and the fish transporting barrel was placed into the adaptation area of the test water tank to continue adapting for 30 minutes. The bottom of the fish transporting barrel was opened through the pull ropes; the fish transporting barrel was lifted out slowly; the test was started.

[0048] The distribution positions of the fish was observed by using the infrared camera. The distribution positions of the fish were recorded for 24 hours continuously. The number of the fish in each test area was recorded every other 5 minutes.

[0049] 3. Test data acquisition and preference index calculation: the percentages of the occurrence frequency of the schizothoracids in white light, green light, red light, and blue light were calculated through video playback by using a formula:

P=(n/N)*100%

[0050] where P is the percentage of the occurrence number in each area, n is the occurrence frequency of the test fish in each area, and N is the total occurrence frequency of the test fish in all test areas in the whole test period.

[0051] 4. Maintenance and cleaning of the device: after the end of the test, the test device and supporting systems were detached, cleaned and maintained, and then, were stored in categories.

[0052] In the test, the research on light preference is carried out by taking the schizothoracids with an average body length of 20 cm as an object, and the light is set as white light, green light, red light, and blue light. The test of each fish is recorded for 24 hours, and six groups are repeated. The test results are as follows, and finally, the percentages of the occurrence frequency of the schizothoracids with this specification in white light, green light, red light, and blue light are respectively: 37.2%, 19.7%, 13.2%, and 29.9%. The results show that the schizothoracids prefers white light and blue light, and does not obviously prefers red light and green light. Researches have shown that blue light can relieve the pressure of Oreochromis niloticus and increase its reproductive capacity (Maia & Volpato, 2017), and Micropterus salmoides repels red light (Brittany et al., 2016). The occurrence frequency is used for statistics in relevant researches, but the tests of the relevant researches are carried out in still water, which ignores the influence of non-directional swimming of fish on the test. Rectangular test equipment without an adaptation area is adopted in the test of the Micropterus salmoides, and errors of test statistics are ignored. The schizothoracids lives at the bottom of a water body. Spectral colors are filtered step by step after sunlight passes through the water body. Most light on the surface of the water body is red light, and most light at the bottom of the water body is blue light (Bowmaker, 1995). So, the preference of the schizothoracids for blue light is consistent with the fact. The preference for white light may be because white light is composite light, so fish also develop a preference for it.

TABLE-US-00001 White Green Red Blue Number of test fish light (%) light (%) light (%) light (%) 1 37.3 36.7 10.8 15.2 2 71.7 13.0 5.1 10.5 3 40.3 20.7 13.5 25.5 4 15.9 16.7 18.6 48.8 5 37.6 24.2 19.8 18.4 6 20.4 6.9 11.6 61.1 Total 37.2 19.7 13.2 29.9

Embodiment 3

[0053] Application of a test device for noninvasive testing of fish preference in substrate preference test of schizothoracids:

[0054] 1. The test water tank in the device of Embodiment 1 was filled with water, the water inlet amount and the water outlet amount were regulated through the water circulating system, and different substrates (cement pool bottom, crushed gravel, pebbles, and cobbles) were arranged in the test areas to create required environments.

[0055] 2. Fish preference test: one test fish was placed into the fish transporting barrel to adapt for 30 minutes, and the fish transporting barrel was placed into the adaptation area of the test water tank to continue adapting for 30 minutes. The bottom of the fish transporting barrel was opened through the pull ropes; the fish transporting barrel was lifted out slowly; the test was started.

[0056] The distribution positions of the fish were observed and recorded by using the infrared camera. The distribution positions of the fish were recorded for 24 hours continuously. The number of the fish in each test areas was recorded every other 5 minutes.

[0057] 3. Test data acquisition and preference index calculation: the percentages of the occurrence frequency of the schizothoracids in the test areas with the cement pool bottom, the crushed gravel, the pebbles, and the cobbles were calculated through video playback by using a formula:

P=(n/N)*100%

[0058] 4. Maintenance and cleaning of the device: after the end of the test, the test device and supporting systems were detached, cleaned and maintained, and then, were stored in categories.

[0059] In the test, the substrate preference research is carried out by taking the schizothoracids with an average body length of 20 cm as an object, and the substrate is arranged as the habitats with the cement pool bottom, the crushed gravel, the pebbles, and the cobbles. The test of each fish is recorded for 24 hours, and six groups are repeated. The test results are as follows, and the percentages of the occurrence frequency of the schizothoracids in the habitat areas with the substrates arranged as the cement pool bottom, the crushed gravel, the pebbles, and the cobbles are respectively: 31.0%, 38.9%, 6.0% and 24.1%. The results show that the schizothoracids prefers the crushed gravel. The schizothoracids usually lives in a small slow flowing bay in a river, usually feeds in a riverbed with the substrate of sand and gravel, and spawns in a fast flowing gravel river in reproduction period. The operation period of the test is July and August, and the obtained preference of the schizothoracids for the crushed gravel is consistent with the fact.

TABLE-US-00002 Number of test fish Cement pool Crushed (%) bottom(%) gravel (%) Pebbles(%) Cobbles 1 2.8 51.4 6.9 38.9 2 23.6 50.0 6.9 19.5 3 65.3 19.4 4.2 11.1 4 40.3 37.5 6.9 15.3 5 38.9 38.9 5.6 16.6 6 15.3 36.1 5.6 43.0 Total 31.0 38.9 6.0 24.1

[0060] The descriptions above are merely non-limited embodiments of the present disclosure. A number of variations and modifications may be made by those of ordinary skill in the art without departing from the conception of the present disclosure or making creative effort, and all fall within the scope of protection of the present disclosure.