Reproduction & Recovery - Energetics

Transcription

1 Reproduction & Recovery - Energetics Iteroparity & Semelparity Iteroparity- (perennial) reproduces more than once. Semelparity- (annual) reproduces only once. 1

2 Crespi, B.J. and R. Teo Comparative phylogenetic analysis of the evolution of semelparity and life history in salmonid fishes. Evolution 56(5) Which strategy evolved first? Lower degree of repeat breeding linked to higher reproductive investment. Tradeoff between high juvenile survival and adult survival at least in salmonids. Energy & Reproduction Evolution of diadromy (anadromy, catadromy, amphidromy) Energy investment Lifetime reproductive fitness 2

3 Fish Energy Lipid (26.4 kj/g) Protein (20.1 kj/g) Lipid Very little carbs Protein Fleming, I.A. and J.D. Reynolds Salmon breeding systems. Pages In A.P. Hendry and S.C. Stearns. Evolution illuminated salmon and their relatives. Oxford University Press, USA. 3

4 Fleming, I.A Pattern and variability in the breeding system of Atlantic salmon, with comparisons to other salmonids. Canadian Journal of Fisheries and Aquatic Sciences 55 (Suppl. 1):59-76 Fleming, I.A. and J.D. Reynolds Salmon breeding systems. Pages In A.P. Hendry and S.C. Stearns. Evolution illuminated salmon and their relatives. Oxford University Press, USA. Gray Anadromous Open Resident 4

5 Anadromous vs. Resident Why do you think some salmonid populations have both anadromous & resident individuals within the same population? Anadromous vs. Resident Why do you think some salmonid populations have both anadromous & resident individuals within the same population? All juveniles do not grow & accumulate [energy] equally in freshwater due to differences in genetics & environment. Get a fish fat enough and it won t move because the need has been quelled. In contrast, a hungry fish will move as far as necessary to get fat. J.R. McMillan 5

6 Costs of Reproduction Gonadal maturation - It costs more to build eggs than sperm Migration Fasting Competition Guarding Post-spawning Semelparity = no recovery Iteroparity = energy replacement via feeding Gonadal recrudescence (renewed activity) 6

7 Rideout, R.M., and Tomkiewicz Skipped spawning in fishes: More common than you might think. Marine and Coastal Fisheries Dynamics, Management, and Ecosystem Science 3: Consecutive (annual) vs. skipped spawning Reasons for skip spawning: 1. Sterility 2. Intersex (when it is not supposed to be) 3. Disease, parasites, etc. 4. Physiologically & energetically not ready Skipped Spawning & Population Dynamics Not accounting for skipped spawners could result in a overestimation of annual production (4-41%). Adjusting the SSB for skipped spawners in Atlantic cod did not improve the stockrecruitment relationship. Why? 7

8 Physiology of Spawning & Recovery in Snake River Steelhead trout (Oncorhynchus mykiss) Steelhead Anadromous Iteroparous Degree of iteroparity is highly variable (<1.0% to >70%) In Snake River <2.0% 8

9 Steelhead Kelt Research Conservation tool Increase gene flow Reconditioning Historically low? Energy Use & Recovery Goal: Evaluate how much energy & what type of energy is used during reproduction. Where is the bulk of energy used? How much energy remains? What is the physiological capacity for recovery? 9

10 Energy use 10

11 Reproduction vs Feeding Many species, not just migratory fish reduce feeding at the time of reproduction Steelhead studies showed GI stasis and lack of structure for absorption at the time of maturity. mature Good kelt 11

12 Profile of Energy Storage Use of destructive sampling of tissues Use of blood metrics non lethal approach Proximate analysis Mass Balance H 2 O Lipid Protein Ash PROTEIN LIPID ASH H 2 O 12

13 Total energy Lipid + Protein PROTEIN LIPID ASH H 2 O Predicting Energetic Status Model: Total Body Energy = βo + β1 * White Muscle Reconstructing Steelhead Bodies Fillet & Carcass Total Body 13

14 Total Body vs White Muscle Energy Total Body Energy (kcal/gram wet wt.) r 2 = Model: Total Body Energy = *(White Muscle Energy) LGR Kelt (N=11) Celilo (N=7) Linear Regression White Muscle Energy (kcal/gram wet wt.) Total Body Energy (kcal/g wet wt.) Total Body Energy vs. White Muscle Lipid Lethal Samples SY09-SY11 (N=429) Linear Regression (r-square=0.80) White Muscle Lipid (%) 14

15 Total Body Energy (kcal/g wet wt.) Total Body Energy vs. White Muscle Protein Lethal Samples SY09-SY10 (N=429) Linear Regression (r-square=0.80) White Muscle Protein (%) Total Body Energy vs Water 3000 Total Body Energy (kcal/g wet wt.) Coefficients: b[0] b[1] r ² White Muscle Water (%) 15

16 Energy Profile By Phase Total Body Energy (kcal/g wet wt.) JUN-SEP (N=14) OCT-DEC (N=60) JAN-MAY (N=186) APR-JUL (N=153) Early Early-Mid Spawners Kelt Blood Non-lethal Plasma Factors: Nutritional Stress Tissue Damage Electrolytes 16

17 Total Energy vs. Plasma Protein Total Energy (kcal/g wet wt.) Below Detection Limit (BDL): Gritman & PAL (<2.5 g/dl) Protein (g/dl) Logarithmic Regression (R-square = 0.48) Early (N=10) Early-Mid (N=55) Spawning (N=151) Kelt (N=152) Total Energy vs Plasma Cholesterol 3000 Total Energy (kcal/g wet wt.) Below Detection Limit (BDL): Gritman & PAL (<10mg/dL) Logarithmic Regression (R-square = 0.68) Early (N=10) Early-Mid (N=55) Spawning (N=151) Kelt (N=152) Cholesterol (mg/dl) 17

18 Total Energy vs Plasma Triglycerides Total Energy (kcal/g wet wt.) Below Detection Limit (BDL): Gritman & PAL (<10mg/dL) Triglycerides (mg/dl) Logarithmic Regression (R-square = 0.70) Early (N=10) Early-Mid (N=55) Spawning (N=151) Kelt (N=152) Selective comparison with shorter distance migratory stocks 18

19 Coastal vs Inland Situk River, AK Snake River, WA & ID Plasma Comparisons Good female kelts Natural origin (adipose intact) System N Length (cm) Snake 50 Median 60.5 Range Potlatch 47 Median 68.9 Range Clearwater 25 Median 75.0 Range Situk 24 Median 79.5 Range

20 Tissue Sampling All sexes Fresh mortalities Poor condition kelts System Poor condition kelts Instream kelt mortalities Situk 0 11 Potlatch 0 5 Upper Clearwater 0 0 Lower Granite Dam 31 0 Total Plasma Protein (Chi-Square) Above Below detection detection System N limits % limits % Situk River Upper Clearwater weirs Significance α = 0.05 No difference Lower Granite Dam No difference Potlatch weirs

21 Plasma Cholesterol 300 Cholesterol (mg/dl) N = 50 N = 47 N = 25 N = 24 L. Granite Potlatch U. Clearwater Situk System Plasma Triglycerides 700 Triglycerides (mg/dl) N = 41 N = 46 N = 25 N = 24 L. Granite Potlatch U. Clearwater Situk System 21

22 Plasma Calcium 20 Calcium (mg/dl) N = 50 N = 47 N = 25 N = 24 0 L. Granite Potlatch U. Clearwater Situk System Plasma Glucose 300 Glucose (mg/dl) N = 50 N = 46 N = 25 N = 24 0 L. Granite Potlatch U. Clearwater Situk System 22

23 Electrolytes Comparison of Weir Fish a a b Phosphorous (mg/dl) Magnesium (mg/dl) a b a 200 a b a Chloride (mmol/l) Sodium (mmol/l) Potlatch R. Fish Cr. Situk R. Potlatch R. Fish Cr. Situk R. Migratory Mortality Snake vs Situk Total Body Energy (kcal/g wet wt.) POOR ONLY (N=9) POOR ONLY (N=19) POOR ONLY (N=3) WEIR MORT (N=5) WEIR MORT Males only (N=11) At ~ 1000 kcal/g of wet tissue wt. kelts may be at the limits of their energy reserves regardless of the system they come from. LGR SY09 LGR SY10 LGR SY11 Potlatch Situk 23