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Relationship: 2013
Title
Increased Mortality leads to Decrease, Population growth rate
Upstream event
Downstream event
AOPs Referencing Relationship
| AOP Name | Adjacency | Weight of Evidence | Quantitative Understanding | Point of Contact | Author Status | OECD Status |
|---|---|---|---|---|---|---|
| Acetylcholinesterase Inhibition leading to Acute Mortality via Impaired Coordination & Movement | adjacent | Allie Always (send email) | Under development: Not open for comment. Do not cite | |||
| Acetylcholinesterase inhibition leading to acute mortality | adjacent | Moderate | Moderate | Cataia Ives (send email) | Under Development: Contributions and Comments Welcome | Under Development |
| Deiodinase 2 inhibition leading to increased mortality via reduced posterior swim bladder inflation | adjacent | Moderate | Moderate | Brendan Ferreri-Hanberry (send email) | Under Development: Contributions and Comments Welcome | WPHA/WNT Endorsed |
| Deiodinase 2 inhibition leading to increased mortality via reduced anterior swim bladder inflation | adjacent | Moderate | Moderate | Arthur Author (send email) | Under Development: Contributions and Comments Welcome | WPHA/WNT Endorsed |
| Deiodinase 1 inhibition leading to increased mortality via reduced posterior swim bladder inflation | adjacent | Moderate | Moderate | Agnes Aggy (send email) | Under Development: Contributions and Comments Welcome | WPHA/WNT Endorsed |
| Deiodinase 1 inhibition leading to increased mortality via reduced anterior swim bladder inflation | adjacent | Moderate | Moderate | Allie Always (send email) | Under Development: Contributions and Comments Welcome | WPHA/WNT Endorsed |
| Thyroperoxidase inhibition leading to increased mortality via reduced anterior swim bladder inflation | adjacent | Moderate | Moderate | Evgeniia Kazymova (send email) | Under Development: Contributions and Comments Welcome | WPHA/WNT Endorsed |
| Thyroperoxidase inhibition leading to altered visual function via altered retinal layer structure | adjacent | Moderate | Moderate | Allie Always (send email) | Open for citation & comment | EAGMST Under Review |
| Thyroperoxidase inhibition leading to altered visual function via decreased eye size | adjacent | Evgeniia Kazymova (send email) | Under development: Not open for comment. Do not cite | Under Development | ||
| Thyroperoxidase inhibition leading to altered visual function via altered photoreceptor patterning | adjacent | Cataia Ives (send email) | Under development: Not open for comment. Do not cite | Under Development | ||
| Inhibition of Fyna leading to increased mortality via decreased eye size (Microphthalmos) | adjacent | High | High | Brendan Ferreri-Hanberry (send email) | Open for citation & comment | |
| GSK3beta inactivation leading to increased mortality via defects in developing inner ear | adjacent | High | High | Cataia Ives (send email) | Open for citation & comment |
Taxonomic Applicability
Sex Applicability
| Sex | Evidence |
|---|---|
| Unspecific | Moderate |
Life Stage Applicability
| Term | Evidence |
|---|---|
| All life stages | High |
Increased mortality in the reproductive population may lead to a declining population. This depends on the excess mortality due to the applied stressor and the environmental parameters such as food availability and predation rate. Most fish species are r-strategist, meaning they produce a lot of offspring instead of investing in parental care. This results in natural high larval mortality causing only a small percentage of the larvae to survive to maturity. If the excess larval mortality due to a stressor is small, the population dynamics might result in constant population size. Should the larval excess be more significant, or last on the long-term, this will affect the population. To calculate the long-term persistence of the population, population dynamic models should be used.
| ID | Experimental Design | Species | Upstream Observation | Downstream Observation | Citation (first author, year) | Notes |
|---|
| Title | First Author | Biological Plausibility |
Dose Concordance |
Temporal Concordance |
Incidence Concordance |
|---|
Biological Plausibility
Dose Concordance Evidence
Temporal Concordance Evidence
Incidence Concordance Evidence
Uncertainties and Inconsistencies
- The extent to which larval mortality affects population size could depend on the fraction of surplus mortality compared to a natural situation.
- There are scenarios in which individual mortality may not lead to declining population size. These include instances where populations are limited by the availability of habitat and food resources, which can be replenished through immigration. Effects of mortality in the larvae can be compensated by reduced competition for resources (Stige et al., 2019).
- The direct impact of pesticides on migration behavior can be difficult to track in the field, and documentation of mortality during migration is likely underestimated (Eng 2017).
- Assuming other relevant demographic parameters are available, the effect of increased mortality rates on population status can be quantitatively predicted using standard population modeling approaches.
- Stage population matrix models (Caswell, 2000) simulate population growth rates based on age-specific parameters and can be adapted to a range of species (Pinceel et al., 2016). For zebrafish, individually based models (IBM) have been developed to link responses at the individual level to the population level (Beaudouin et al., 2015). However, authors agree that survival is one of the most uncertain parameters in the model and more research on the topic is needed.
Response-response Relationship
Time-scale
Known Feedforward/Feedback loops influencing this KER
Taxonomic: All organisms must survive to reproductive age in order to reproduce and sustain populations. The additional considerations related to survival made above are applicable to other fish species in addition to zebrafish and fathead minnows with the same reproductive strategy (r-strategist as described in the theory of MaxArthur and Wilson (1967). The impact of reduced survival on population size is even greater for k-strategists that invest more energy in a lower number of offspring.
Life stage: Density dependent effects start to play a role in the larval stage of fish when free-feeding starts (Hazlerigg et al., 2014).
Sex: This linkage is independent of sex.